Whilst recently researching the wildflower families, I fell down a fruit-shaped rabbit hole.  And it is because of the amount of variety shown in the fruit of the Rosaceae, or rose family.

Japanese rose Rosa rugosa

For more on what makes a plant a member of the Rosaceae, check out my recent blog Wildflower families: Rosaceae.

Where to start?  There’s a lot of variety, and taking a look at my Fruit variety and terminology blog might help.

Rosaceae Fruit: Aggregate Fruit

Rosaceae fruit are one to two seeded, and often form together into aggregates, or aggregate fruit.  Think of a blackberry or a raspberry.  Each of those little lumps (or drupelets) houses a seed.  They clump together to form what we see as one fruit, although it is an aggregate of many.  Think how many seeds you find when eating one blackberry!

Jersey Post copyright 2027 Jersey bramble Rubus caesarius

If you have time to spare, have a look at my step by step blog on painting a blackberry.

Rosaceae Fruits: Drupes

Some other Rosaceae grow drupes.  A drupe is a fleshy fruit which has a thin skin and grows around a central hard stone.  Inside the stone (or pip, or kernel) is the seed.

Plum Prunus prunus fruit

Plums and cherries are drupes.  In the states, the term “stone fruit” is used.  This refers to any soft fruit with a woody stone, such as apricots and peaches.

Peach Prunus persica with stone (and seed) removed

Rosaceae fruits: Aggregates of Achenes

Some have aggregates of single-seeded achenes.  Some of these have spines which catch onto fur for seed dispersal.  These are actually called awns, and are formed from the persistent remains of the style.

Piri Piri bur Acaena novae-zelandiae seedhead and individual achene with awns

Other examples include Herb bennet, Geum, and Mountain avens.

Water avens Geum rivale showing flower and seed head with awned achenes

Others, like Meadowsweet, twist their achenes together into a spiral.

Potentilla seed heads look a lot like those of the Ranunculaceae family, an assembly of achenes borne in a globe-like arrangement.

Rosaceae Fruit: The Pseudo-fruit (Rosehip)

Rosehips are not made from the carpels of a flower.  The seeds within are formed from carpels, with their thin coats.  But the red or orange fleshy part of a rosehip is called a hypanthium.  It is just a fleshy shell, housing the real fruit, the achenes (formed from carpels), each bearing one seed.  The hypanthium is formed from swollen receptacle flesh.

Japanese Rose Rosa rugosa rosehip cross section

The receptacle is the part of the plant where the flowering parts are attached, not the female flower parts themselves.  Receptacles lie below the flowering structure, and explains why we see that distinctive brown bit at the “bottom” of a rosehip.  They are the remnants of the calyx and other flowering structures, and if you look closely you can sometimes see old stamens.  Which makes that the “top” of the pseudo fruit, I suppose.

Rosehip anatomy diagram

Rosaceae Fruit: The Pome

One of the most commercially important Rosaceae, the apple, carries its’ seeds in a Pome.  A pome is a swelling of the receptacle, not the carpel.  It is built of several hypanthium (enlarged receptacle) which have grown together.

At the centre of this we find the pericarp which contains five to thirteen seeds (it’s commonly known as the apple core), depending on how successful pollination was.

Diagram showing the structure of the Pome (apple)

So next time you eat an apple or a pear, remember that the distinctive brown bit at the “bottom” is the residual flowering parts, specifically the calyx.

Pear sprig with blossom and fruit Pyrus communis

For more on pomes, check out this blog from Where the spruce eats.  To be sure you can tell your pome from your drupe, take a look at this blog from Toronto botanical garden.

Rosaceae Fruit: The Strawberry

The strawberry bears its’ seeds on the outside, and in fact every yellow seed is a strawberry fruit.  The fleshy part (which we eat so cheerily) is made from swollen receptacle tissue, rather like the apple (a pome).

Wild strawberry Fragaria vesca with external fruits and seeds on a swollen receptacle

However, the big difference is that the seeds of the strawberry are on the outside not the inside, and it is the only fruit which does this.  It is therefore not only delicious but also remarkable.

Conclusion

This blog is far from exhaustive, and I have no doubt I could find enough to write an entire blog about the core of an apple.  I hope this serves as an introduction to the variety and fascinating structures of the fruit of the  Rosaceae.

Sketchbook study of the Dog rose Rosa canina

The post Rosaceae Fruit appeared first on Lizzie Harper.

Plants have been on this planet for more than 500 million years, first appearing as red seaweeds and diversifying into the plethora of forms and species we share our planet with today.

FSC Guide to Ancient Woodland plants I illustrated showing a whole range of plants

Plant Evolution time line: Non-flowering plants

If we follow a time-line, we can have some idea of the course of plant evolution on earth.

Let’s start way way back, in the Ordovician, about 500 million years ago.  Nothing grew on land, but in the oceans algae, which we recognize as red seaweeds were growing.  Green plants evolved from these, and adapted into more algaes and plants we still have today, like the Charophytes.

Jump to 470 million years ago, the Silurian.  Plants have colonized land!  They still need water for reproduction, and can’t grow to enormous sizes, but the green takeover has begun.  In this time we see the emergence of Bryophytes: Mosses, liverworts, and hornworts.

Grimmina pulvinata and Tortula muralis

The next enormous milestone in plant evolution is the development of vascular tissue.  Plants are now able to grow tall, creating forests.  Clubmosses (or Lycopods, they’re not mosses at all) now emerge in the fossil record, about 350 million years ago.  Lycopods now are small plants, but at their peak they could grow into trees up to 30m tall.

Vascular vs non vascular plants diagram showing cross section of the stem with vascular bundles

Ferns and Horsetails emerge next.  Enormous tree ferns change the land,  shading out the bryophytes.  Even today, tree ferns can be enormous, and back in the Carboniferous they could grow to gigantic sizes.  They still need water for spore dispersal, but are able to colonise drier habitats.

Plant Evolution time line: Seed producing plants

A massive change occurs; the seed evolves.  This is, as Chris Thorogood puts is, “a little plant within a box”.  Suddenly plants can live in dry environments.  They can live as dormant seeds for years.

Gymnosperms; the conifers, cycads, and ginko appear around 320 million years ago, in the Permian.  Their seeds aren’t enclosed in a fruit, but in cones.

Jack Pine Pinus banksia tree

Jump forward to the Triassic and Jurassic 280 million years ago, and the Cycads are in the ascendency.

Plant Evolution time line: Flowering plants

No-one knows quite when, but around 130 to 100 million years ago something extraordinary happens.  Flowering plants appear in the fossil record.  With tough seeds, flowers for pollinators, and the ability to exploit almost every habitat on earth; these take over.  These comprise Magnoliids, Paleoherbs, Monocots and Eudicots.  And they take over the planet, remaining dominant to this very day.

Plant evolution: Red algae

Red algae are marine seaweeds.  It’s a bit of a catch-all phrase and covers most of the red seaweeds, unicellar and multi-cellular organisms.  Brown seaweeds are a little different, and are thought to have evolved through endosymbiosis with red algae.  A common red algae is Dulse, which is also edible.

Dulse Palmaria palmata

Plant evolution: Green algae and Charophytes

On a microscopic level, tiny green algae can be stunning.  Many, like Desmids, are unicellular.  Take a look at this film of Volvox (some Volvox are unicellular whilst others live colonially) or photos of Pediastrum, a green algae living in colonies

Some green algae are larger, forming mats in ponds and pools.

Charophytes appear in this group, and are considered the oldest living relatives of land plants.  They pop up in the fossil record 500 million years ago and have remained unchanged until now.

Delicate Stonewort Chara virgata

Plant evolution: Bryophytes

Bryophytes are mosses, liverworts and hornworts.  I’m yet to illustrate a liverwort or a hornwort, but they can be really pretty, like green leathery cloaks across the ground.  They like moist environments, and often decorate cliffs by streams and waterfalls.

Mosses are subjects that I have been asked to illustrate.

Red bog moss Sphagnum capillifolium tuft

For many millions of years, land masses on planet earth were covered in moss, without any other plants in existence.  It is an almost impossible mental image.  Moss reproduce with spores, and need water to reproduce.  Spores appear in tiny capsules which are held above the blanket of moss below.  Bryophytes are haplodiploid, which means there’s an alternation of haploid and diploid generations, and like all the other early plants they have neither flowers nor seeds.

Common haircap moss Polytrichum commune

Plant evolution: Lycopods

Lycopods come to dominate after the mosses and liverworts.  They have vascular tissue so could grow high, into enormous tree-like structures.

The Club mosses we see today are far smaller, and can grow horizontally.  You might see them growing on moorland or heath, especially in Scotland.  For more the Stag’s horn clubmoss, one of our commonest Lycopods, click here.

Stags horn clubmoss Lycopodium clavatum

Plant evolution: Ferns & Angiopteris (Tree ferns)

Ferns are still much in evidence today, again, favouring moist habitats where their spores can fertilize aquatically, often in a thin film of water.  There’s an abundance of variety in the form of ferns, some having divided and sub-divided leaves, others with smooth complete fronds.

Harts tongue fern Asplenium scolopendrium

Tree ferns can grow to massive heights to this day, in the right undisturbed habitats.  There are enormous ones in the rain forests of Kalinga, Philippines.

Illustrating Bracken Pteridium aquilinum

Plant evolution: Horsetails

Horsetails are often referred to as “living fossils”, and they are indeed truly ancient.

They produce spores from a cone or strobilus.  Most prefer moist environments, and in the UK they rarely grown higher than about 1m tall.  In Mexico, some species reach over 8m!

Horsetails have a distinctive appearance, with bristles or leaves coming off a central ridged stem.  For more on horsetails click here.

Water horsetail Equisetum fluviatile

Plant evolution: Gymnosperms

Gymnosperms are the first plants to bear seeds.  This enabled a massive explosion in the places these colonising plants could grow.

They’re pollinated by wind, and seeds are borne in cones.  The seeds themselves are referred to as “naked” as they’re not enclosed in a fruit.  However, animals have evolved to exploit this rich food source – just consider the Red squirrel or the Crossbill.

Dwarf Pine subspecies cones

Conifers, Cycads, and the Ginko tree (yet another plant always called a “living fossil”) are all Gymnosperms.

Gingko Ginko biloba

Of course, the most enormous plants on earth are Gymnosperms; the Giant Redwood tree.  These heights owe everything to the earlier evolution of vascular tissue which put ferns, horsetails and eventually Gymnosperms head and shoulders above the competition.

Giant Redwood Sequoia sempevirnes

Plant evolution: Flowering Plants (Angiosperms)

Modern seed bearing plants are incredibly successful, clothing and dispersing their seeds in an astonishing variety of ways.  Many advertise their pollen to insects, birds and mammals with complex and glorious flowering structures.  Others rely on the wind.  There’s not enough room to even begin a comprehensive overview here, but I’ll touch on the four main groups of flowering plants.

Overview of a Eudicot flower

Plant evolution: Flowering Plants: Magnolias

Magnolia are considered one of the oldest flowering plants.  They’re truly ancient, dating back 95 million years.  Although they have petals and sepals, these aren’t clearly distinguished from each other.  They are pollinated by little beetles.

Magnolia grandiflora

One of the many magnificent facts about the Magnolia is the longevity of its’ seeds.  Remember how we referred to a seed as a “box with a plant inside”?  Well, magnolia seeds which fell from the tree thousands and thousands of years ago can be planted up, and will grow to a successful adult tree.  This blows my tiny mind.

Magnolia

Plant evolution: Flowering Plants: Paleoherbs

Paleoherbs are also known as Basal angiosperms and, like Magnolia, are very ancient.  This whole group was entirely new to me, and exists as many of the plants referred to as Paleoherbs share features of the eudicots and of the monocots.  Plants in this group include the Aristolochiales (Dutchman’s pipe), Piperales (Black Pepper, Wild ginger), and Nymphaeales (lotus and Waterlilies) For more on Paleoherbs, have a look at the introduction from Berkeley College, California.

White waterlily Nymphaea alba

Plant evolution: Flowering Plants: Monocots

And so we arrive, finally, at the true flowering plants.  These are divided into two main groups, the monocots and the eudicots.

Monocots tend to have parallel leaf veins, leaves often grow from the base of the plant, flowers are three-partite.  They grow from grains or bulbs.

Spring squill Scilla verna

Orchids, flowering blubs like tulip, Arums, iris, and my favourites the grasses, sedges and rushes are all monocots.  It’s worth remembering most of our food crops (rice, maize, wheat, barley, rye, oats) are also monocots.

Grasses: Cocksfoot Dactylis glomerata, Deschampsia, Agrostis

Plant evolution: Flowering Plants: Eudicots

Eudicots mostly have leaves with a branching or netted vein pattern.  Their flowers have parts (eg, stamens, petals) in multiples of 4, 5, or 7.  Plants grow from a seed with two sides (think of a bean seed).

Some Eudictot families have heads with lots of flowers held together, in an inflorescence; not just one flower on the end of a stalk.  This is true of the Asteraceae, the daisy family.  Each of the outside “petals” is a ray floret, each tiny spot in the centre is a mini flower.  Take a look with a hand lens, it’s amazing.

African daisy Gerbera

75% of flowering plants are Eudicots, and they cover plants as diverse as the Cactus to the Lime tree, the Creeping thistle to the Potato, the Pomegranate tree to the daisy.

Prickly pear Opuntia ficus-indica

For more on the differences between Monocots and Eudicots, please check out my blog.

It’s the combination of that strong, safe seed; and co-opting animals or the wind to help pollination that’s led to this dominance.  Flowers are a by product that we get to enjoy, and to illustrate.  Fruit and nuts work for seed distribution, and feed us.  With these adaptations there are hardly any habitats on earth that the Eudicots can’t exploit.  They are indeed dominant.

Common Blue-sow thistle Cicerbita macrophylla

Conclusion

But I’m more in awe of the amazing variety and persistence of the plants that live on this planet.

From the unicellular green algae, still living in ponds and puddles as they did 400 million years ago.  To the Charophytes, unchanged and still growing in waterways.  The mosses which once blanketed the world and which still swaddle vast tracts of tundra and moorland.  Ferns, in all their beauty and variety remain massively successful – just look at Bracken on UK hillsides.  The strangely beautiful Lycopds and Horsetails.  Conifers and cycads, shedding cones as they have done for millenia.  Magnolia, enticing beetles with pollen all those millions of years ago.

Sphagnum magellicum

Please don’t disregard these plants, simply because they’ve not put their energies into growing pretty flowers to entice pollinators.  Instead, be awed by the majesty and history of the entire varied kingdom.  And perhaps we should all feel a little humbled by these temporal giants, too.

Enormous thanks are due to Chris Thorogood and to Julia Trickey – without Julia’s amazing series of talks I’d have never got to learn any of this fascinating information.  And without Chris and his extraordinary knowledge and ability to engage and enthuse, I wouldn’t have even known where to begin.

Euglena, a unicellular aquatic green algae

The post Plant Evolution: A brief overview appeared first on Lizzie Harper.

Sketchbook pages

FOR have commissioned several sets of invasive species over the years, and favour the sketchbook approach.

For me, this is a treat.  Sketchbook studies incorporate all the important aspects of a plant that help you to identify it.  However, you can pick and choose which elements to work up to a finished level.  This gives me an enormous amount of freedom to play about with composition, and to focus on aspects of the plant that really interest me.  There’s a gallery of these on my website, and many originals (including the Heath star moss) are available to buy.

Himalayan Blackberry Rubus armeniacus for FOR

Illustrating Moss

I’ve illustrated moss before, and always enjoy it.  These plants are so totally different from the normal vascular species I illustrate, and that’s one of the things I love about them.  Their details are tiny, which also appeals to me.  Luckily, I’ve got lots of books on moss (such as Mosses and Liverworts of Britain and Ireland by Atherton, Bosanquet, and Lawley) which are invaluable.

Red bog moss Sphagnum capillifolium

Anatomical details that need including are the shoots which emerge from the main body of the moss, sometimes known as the protonema.  Spores and the shoots bearing them (sporophytes) need to be recorded, along with the spore capsules and their hoods (calyptra).  Individual gametophyte shoots also need illustrating. Stems (also referred to as the caulid or axis) and individual leaves (phyllids) need detailing, along with information on the cellular structure of the leaves.

There seem to be quite a lot of different terms for the same structures, depending on which bryologist you ask.  For this reason, do excuse any botanical mistakes I might make in this blog!

Sphagnum capillifolium details

Illustrating these elements requires pretty full on dives into my moss books, and often the community of bryologists on Twitter or the British bryological society help out.  One day, I need to get one of these lovely and eminent botanists to write a guest blog on the theme “Introduction to Mosses”.  It’d be invaluable for me, as well as other moss-dabblers!

Heath star moss: Specimen

The first thing to do is to get my hands on some actual Heath star moss.  I’m extremely fortunate to know one Ray Woods, a top moss expert, who lives nearby.  Despite the world being in Covid-19 lockdown, he found some Campylopus introflexus on his greenhouse roof and sent it to me.

Next, I drew it up in pencil and, once I got the ok from the client, could apply some colour.

Heath star moss: Is it wet…or is it dry?

One of the quirks of this particular species is that it looks totally different when it’s wet and when it’s dry.  When wet, it has a bright green, star-like appearance.

Wet Heath star moss Campylopus introflexus

When it’s dry it looks almost black, and very scaly,  Each phyllid (leaflet) has a long, glassy tip.  These bend at sharp angles when they’re dry.  Tons of these tiny “leaves” with their white, spindly points makes a patch of Heath star moss look almost hoary.  This was an absolute pain to draw, but become easier to understand, visually, once I got some colour on the illustration.

Heath star moss Campylopus introflexus

The two illustrations above are of the exact same specimen.  I didn’t have a lot of the moss, so only broke off a fragment and allowed it to dry in the airing cupboard.  The rest I kept moist as I needed to illustrate details of the spore capsule and phyllids, which are easier to manage when wet.

Heath star moss: Individual shoots

As well as a clump of moss, I needed to include details of the individual shoots when wet and dry.  The main focus here has to be the points.  I’m tempted to call them awns, as one would do if talking about grasses, but am pretty sure they have their own specific name somewhere….  These tips are always bent, but become very recurved when the moss is dry.  It’s a diagnostic of the species; if these spines recurve more than 90 degrees then it’s probably the Heath star moss.

Heath star moss Campylopus introflexus shoots

I also include top views of the shoot (also referred to as a fascicle.  See, I told you there were lots of different words for the same things!), although this didn’t help much with the dry specimen.

To ensure botanical honesty, these illustrations are both pf the exact same fascilce.

Heath star moss: Cellular details

The next challenge was to look at an individual phyllid.  I had access to good microscopic images from the British bryological society, and thanks to Ray I could also get my compound and dissecting microscope out on real specimens.  Knowing I was working with the correct species is more reassuring than I can possibly tell you.  I am forever indebted to ray who has often given me labelled specimens of moss.

Heath star moss Campylopus introflexus microscopic details

So here is an image of an individual phyllid, and its margin under a higher magnification.  I was keen to have the spine clearly included.  Below are some of the British bryological society reference photos I was able to use.

The shape of the cells at the edge of the phyllid is often species specific (as in this case), hence including the detail.

Heath star moss: Sporophyte

Illustrating the sporophyte was much easier.  My specimen had a few spore cases, so I had a look at them under the microscope.  I couldn’t identify or get images of any spores, but decided that didn’t matter too much.  The shape and colour of the spore capsule was the main thing.

Heath star moss Campylopus introflexus sporophyte

I think the stems (caulid or axis) might be more wiggly and curled up when the specimen is dry, but as I didn’t see mention of this in the literature I decided not to make that a focus.

Heath star moss; Habit sketch

The easiest part of this sheet was completing the habit sketch.  I had photos of clumps of this moss, and I had my specimen.  I’ve also got a decent idea of what the limestone substrate it’s growing on looks like.  It was a simple matter of collating these resources.

I added a yellow leaf for scale, and decided pretty fast that the habit sketch would be of the moss when it was wet.  Drawing it dry had already made me come close to despair.  In any case, it looks lovely when it’s wet and far less appealing when dried out.

Heath star moss Campylopus introflexus on stone

Conclusion

When the sheet was done, I was really pleased.  It included all the required details, and hung together (more or less) as a composition.

When I illustrate moss, I take one contact lens out so I can see the detail.  I leave the other one in.  A week of doing this left me with my head spinning (but no headaches, luckily).  I was relieved the commission was complete.

Without Ray and the British bryological society there’s no way I’d be able to illustrate mosses.  And I absolutely am on the look out for someone with the skills and willingness to write a guest blog here on the basic anatomy of moss.

But for now, I just look forward to the next time an email pops into my inbox, asking for an illustration of another species of moss.

If you’d like to see how FOR have used my sketchbook studies, please take a look at the PDFs available on their website.  There’s a list at the bottom right.  Telling which species is which is tricky though, my Swedish isn’t any good at all!

The post Heath Star Moss Sketchbook study appeared first on Lizzie Harper.

I recently completed an illustration of Bracken Pteridium aquilinum for a forthcoming Field Studies Council Guide to the flora of Woodlands.  I thought this was the perfect chance to explain the process.

Drawing bracken and Pencil roughs

Bracken is a large plant, some plants stretch to over 2m tall.  The leaves or fronds are sub divided, and each division is divided again.  this is called being tri-pinnate.  And it’s beastly to draw!  Reducing this complexity and size to a sheet of A4 paper is a challenge.

I took two approaches, and drew two versions.  One had the bracken in a clump, as it grows in the wild.

Bracken rough 1

The second shows two separate fronds and made more of the root structure.  This meant working from photos as well as filling my studio with bracken.  Photos are mighty useful for reducing a plant to a manageable size.  However, to guarantee getting the botanical detail correct, you need the plant itself, or at least close up photos.  (For more on working form photo reference, check out my blog).  The client chose this second rough, which I think was the right choice.

Bracken rough 2

Adding colour

So you have your pencil drawing ready yo go.  Surely this is where the hard work begins?  Well, no.

The very fact that the drawing of the bracken was so difficult now works in your favour.  there’s an enormous amount of detail in the drawing.  this means that there are very few large expanses of colour.  It’s these areas that end up needing the hard work.  They require attention to show the lights and darks, and to add texture.

With complicated structures like the bracken, you need do far less to get a good result.

First step is to mix the right green.  In this case I’m using Winsor and Newton watercolour paints.  To get the right green, it’s a mix of Cadmium yellow light, purple, Yellow ochre, Sap green, Cobalt green, and some greenish blue like Pthalo.   Keep mixing until it matches the frond in your hand.

Then all you do is go over your pencil lines with a thin and confident paintbrush line.  Brushes that hold their tips well, like my beloved Winsor & Newton series 7 (number 1) are ideal.  To make sure your lines are crisp, work on a smooth, hot-press paper.  Currently, I’m loving Fluid 100.

Bracken illustration with leaf edges outlined in green. Areas remaining to be outlined will be done in a slightly lighter shade of green.

If you want to add a little extra dimension to the illustration, you can mix two greens.  Make one somewhat lighter than the other.  I do this by adding yellow.  Then choose which side of your frond is the lighter.  Outline these leaves in the same way as before, but this time with the lighter shade. Keep the side of leaf which is lighter consistent across the plant, but be aware it may “flip” as you cross the main stem of the frond.

Tackling stems

You can put in the stems whenever you feel like it.  Sometimes I add them quite early as it ties the illustration together.  Mix a slightly brownish yellow-green.  Outline the stems, with a little more weight to the right side of each stem.  Then dilute your mix with water to make it paler.  Once the stem outlines are dry, paint over the stems with this dilute mix.  You should have stems which look a little darker on the right hand side.  Again, this adds to the feeling of light and shade in the illustration.

Once dry, you may want to add other colours to the stem.  For bracken, this would include the dark brown which appears at the base of the stems.  This needs to be included as it’s species specific.  other ferns may have flaky scales at the base of their stems.  Be sure to include these if they’re present.

Stem completed, returning to the leaves.

Adding body colour to the fronds

Once the outlines are dry, you can add colour.  Mix up a more watery green than before.  Tackling one side of each frond at a time, just paint this on top of your fern.  Allow the paint to be nice and wet.  As it dries, it’ll add its own crisp edges to your outlines and sharpen up the illustration.  Be sure not to do both sides at once.  If the wet paint runs into other areas, it wont look as sharp when it dries.

In the illustration below, the top of the fronds on left hand side have been outlined in a slightly darker green.  The top wash is also been a little darker.  The opposite side of each leaf has a lighter and slightly more yellow colour.  This difference in colour tricks the eye into thinking that the two sides are slightly curled upwards, with one side casting its shadow on the other.  it makes the plant look less flat.

On the other side of the main stem (rachis), flip the pattern of shadows.

I’ve also added some darker green to the areas of the stem which overlap.  Again, this is to add depth to the illustration.

Top washes on the fern are drying

Where the fronds of the bracken leaf overlap, I’ve picked out the shadows in a darker shade of green.  I mix this by adding browns, blues, or purples to the mix.  Be careful with this darker shade, you want it to represent shadow, not to look like the main colour of the plant.

Adding Shadows

Once completely dry, you can add even more definition to the fern by picking out your darkest darks with really quite a deep colour.  I tend to use a mix of purple with cobalt blue.  Be judicious with these dark shades, and remember you’re adding them to add tonality and clarity, not just to muddy and darken the picture.

You can also add the same colour to pick out the darkest shadows on the roots.

Completed Bracken illustration with darkest darks added.

Finished!

And really, that’s it.  If the differences between the sides of the leaves looks too stark, you can add a dilute green top wash to unify them.  If they look too pale, revisit and add another layer of wet green.

Compared to the huffing and puffing involved in getting the leaves of something like a rose or a hazel illustrated, this is a walk in the park.

The drawing is definitely challenging.  But when it comes to the “colouring in”, the intricate details turn our to be your allies.

Bracken Pteridium aquilinum with detail

Other examples

Below are some other examples of ferns done using the exact same approach.

The Hard fern has also had the blunt leaf tips darkened a little with a we-tish mix of cobalt blue.

Hard fern Blechnum spicant

The Male scaly fern (below) has also had a darker shadow laid along the right hand side of the central axis.  This helps draw the eye up the plant.  You can see the same approach we discussed above clearly.  The top of each small frond is darker on one side than the other.  And once you cross the central axis, that pattern flips.

Scaly male fern Dryopteris affinis

With the Maidenhair spleenwort below, a midrib was added to each leaf.  Each leaf was outlined.  It had a midrib painted in.  A flat top-wash of green was added.  And that was it.  In this example I didn’t even need to play about with lighter or darker shades of green.  I just made the leaves at the back of the plant darker by popping a blueish brown shadow on them.

Maidenhair spleenwort Asplenuum trichomanes

Feel free to give it a try.  You might be surprised by how easy it is.  As the for the drawing of any ferns though, I’m afraid that part of the job is just really hard work!

The post Illustrating Bracken and Ferns appeared first on Lizzie Harper.

Halophytes are plants that tolerate or thrive in salty conditions.  I recently finished the illustrations for a chart of seaside flowers, and got to wondering how these plants can survive in these hostile habitats?  Another job, illustrating stamps for a Seaside flowers issue, added to my interest.

This blog had me scouring the internet, and getting more and more fascinated by what I found.  However, I am no expert, and would refer interested readers to the bibliography at the end of the blog for references and further reading.

Sea Bindweed Calystegia soldanella

Salt damage

Salt damages most plants as it messes up the way cells absorb water.  A plant which isn’t adapted for salty (or haline) conditions wouldn’t last long in a salt marsh or coastal area.  Salt water can reduce plant growth and photosynthesis.  It leads to an imbalance of nutrients and ions.  It alters plant hormone production and action.  Most obviously, it makes it hard for plants to regulate their water balance.

Thrift Armeria maritima

Halophytes

Some plants have evolved to survive these harsh conditions.  These are the Halophytes.  They can tolerate a range of salty environments, from salt-marshes to dry and salty deserts.  Their adaptations help them shrug off the effects of salt spray, and allow them to live in soils saturated with salty water.  It’s not every plant that can do this.  Only 1 – 2 % of the world’s flora are halophytes.  Of these, “only 0.25% are reportedly able to complete their life cycles in Saline soils” (Flowers et al 1990, New Phytologist 1990)

(Plants which can’t tolerate salt are called Glycophytes.  This literally translates from the Latin as “Sweet loving plants”.)

Types of Halophyte

There are various classifications of Halophytes, mostly depending on what concentrations of salt they can survive.  There are Obligate halophytes, plants which need salt to grow.  An example of this is the Glasswort, Salicornia.

Common Glasswort Salicornia europaea

There are many more Faculative halophytes.  These plants can tolerate salt, but will also thrive in non-salty conditions.

Some halophytes need wet soil or salt-marshes to survive.  These are termed Hydro-halophytes.  A mangrove tree is the most obvious example.

Mangrove swamp – a haline habitat

Xero-halophytes thrive in dry and salty soils, such as deserts.  They can handle unpredictable rains as well as salty soils.  The Frankincense tree is an example.

Adaptations to Saline environments

Although there aren’t an enormous number of halophytes, they’re distributed across lots of plant families.  It’s believed that the adaptations needed to survive these inhospitable habitats have evolved independently on many occasions.  The fact that so many species have ended up with similar coping mechanisms is yet another example of convergent evolution.

Adaptations: Being a Succulent

Lots of halophytes are succulents.  This means that their stems and leaves are fleshy and watery.  Succulent plants have fewer cells, and these cells are longer than those in other plants.

Hottentot fig Carpobrotus edulis

Salt absorbs water, so it’s vital to counteract this.  In succulents, moisture is preserved using lots of these water bearing cells.  These watery cells manage to dilute the concentration of salt in the sap of the cell.  Thin cell walls allow each cell to swell and accommodate its watery burden.

English stonecrop Sedum anglicum

Adaptations: Small leaves

Halophyte leaves are excellent at counter-acting the desiccating effects of salt.  Many halophyte plants have tiny leaves.  These have a small surface area, so less water is lost through transpiration.  Lots of species have few and small stomata.  Again, this helps the plant cling onto water.

Lesser Sea spurrey Spergularia marina

Though small, leaves may be thick, and succulent.  The ratio of water-storing space to surface area is high.

Biting Stonecrop Sedum acre

Thicker epidermal layers are seen in some halophytes, and many have a thick, waxy cuticle which helps to waterproof the leaves.  However, just because plants (like sedums) have a thick waxy cuticle, this does not necessarily mean they can tolerate salty conditions.  Some can, others can not.

Remember, leaves need to keep the water inside, but they also need to protect the plant from the external damage salt spray can inflict.  The thicker epidermis and cuticle do both.

Some halophytic plants sport leaves with low levels of chlorophyll.  Perhaps this contributes to the blue-ish hue of many of their leaves?

Sea Kale Crambe maritima

Adaptations: Secreting salt & Salt glands

Salt levels can be regulated using salt glands.  These excrete salt, either direct onto the leaf surface, or into a discreet gland.  These can be vacuoles of bladder cells, and are often hidden just below the surface of the epidermis.  In some species, these glands burst; in others they break off and fall from the plant, carrying their toxic salt burden with them.

These salt bladders accommodate the build-up of salt or other ions, and allow a plant to exclude certain elements from its tissues.

Sea lavender species have salt glands just below the level of the epidermal cells.

Sea Lavender Limonium vulgare

Salt glands may be specialised Trichomes (outgrowths from the epidermis of a plant).  Lots of coastal plants have greyish blue stems and leaves.  In many cases, they are covered with a wide variety of trichomes.  Some are simple, some are un-branched.  These not only affect leaf temperature and aid water economy, but contribute to that distinctive hue.

Yellow-horned Poppy Glaucium flavum

Adaptations: Tough seeds

Seeds of halophytes have been widely researched, and their viability and ability to germinate in salty conditions is amazing.

Many have thick and waxy seed coats.  Seeds may be large.  However, it is the hormonal regulation and patterns of germination which are most interesting.

Germination times are often very fast, and times of reproduction and germination can be tightly controlled by plant hormones.  Recovery of germination after salt-stress or drought (in xerohylophtes) is rapid.  Flowers and Colmer have done extensive research on this topic.

Greater Sea spurrey Spergularia media

Greater Sea spurrey, whose seed dormancy patterns have been examined extensively by Ungar.

Adaptations: Amazing roots

Roots have an important role to play in salt regulation.  Some halophytes produce pneumatophores, structures which protrude from salty water into the air (see my blog on Root variety for more on this).

Other plants have extensive networks of roots which grow into less salty substrates.  Adventitious roots allow for horizontal growth, which could allow a plant to grow directly above saltier soils.

Marram grass Ammophila arenaria

Adaptations: Accumulate salt then die

A more extreme solution is just to accumulate salt…then die.  Some rush (Juncus) species do this.  They have no means of regulatiing their salt balance.  However, this doesn’t seem to stop them from colonising salty environments and reproducing successfully.

Why choose a salty environment?

Having looked at adaptations to this hostile environment, one has to ask, “why grow there?”  Clearly, the salt is problematic and has required an armory of evolutionary coping mechanisms.  So why spend that energy to exploit such an environment?

Firstly, there’s not a lot of competition.  As stated earlier, 95% of plants can’t survive saline habitats.  That’s 95% less potential competitors for your niche.

Haline habitats may also be lower in predators, and may help keep numbers of vermin down.  In the literature there’s also some suggestion that salty environments can help prevent disease, although I didn’t examine this fully.

Examples of Halophytes

So what plants are halophytes?  It partly depends on your definition, but below are some examples.

In the grass family Poaceae, Marram grass and Cord Grass grow on salty sand dunes.

English Cord-grass Spartina anglica

The Amaranthaceae family includes the obligate halophyte Glasswort.  It also includes Saltwort Salsola kali.

Saltwort

Other members of this family are Pig-weeds, Goose-foot, and Beet.

Sea Beet Beta vulgaris maritima

In the Plumbaginaceae family there’s Sea Lavender

In the Legumes we have the Sea pea, Lathyrus japonicus

Sea pea Lathyrus japonicas

There are databases of halophytic plants, including the Halophyte Database and a list of salt-tolerant plants from the Biosalinity Awareness Project

Why are Halophytes so important in 2020?

Halophytes aren’t just fascinating plants.  They could be vital to us humans, in our rapidly changing world.  Most crops are glycophytes, and are salt-sensitive.  With many places at increasing risk from rising sea levels, crops which are resistant to salty water could have an important role to play.  Research is being done to see if cross-breeding and genetic modification could help develop new salt-resistant crop plants.

(Sea Sandwort, below, is edible.  However, I found no evidence it was being trialled as a salt-resistant crop…as yet!)

Sea Sandwort Hockenya peploides

Salt-affected and land made toxic with heavy metals areas could be cleaned with the help of halophytes.  Some halophytes are able to regulate the ions entering their xylem stream.  These ions include sodium and other elements.    Scientists such as Lutts & Lefevre are researching their potential role as a way to clean heavy metals from the soil. (Lutts & Lefevre 2015  How can we take advantage of halophyte properties to cope with heavy metal toxicity in salt-affected areas?  Annals of Botany 2015).  Halophytes may prove vital in these processes of phytoremediation.

Ecologically, halophytes have an important role to play with land reclamation.  Their networks of tough roots and ability to withstand tidal flooding make them perfect candidates to help re-colonise saline lands.

Sea buckthorn Hippophae rhamnoides

With halophytes helping humanity reclaim salty land, and produce salt-tolerant crops for a rising population in an environmentally changing world; I think it would be hard to over-estimate their importance to our future.

Conclusion

With their ingenious adaptations and ability to colonise salty habitats, halophytes are fascinating.  Couple this with their potential as an important aid to humanity, and they become ever more deserving of our attention.

Below is a list of further reading.  There are many nuances to current research which hasn’t been covered in this blog; issues relating to biochemistry and seed viability amongst them.  Hopefully the bibliography below will allow an interested reader to pursue the topic further.

(Many of these original illustrations are available to buy, just search for them in by name in the “Original Illustrations for Sale” section of my website).

Bibliography

Colmer & Flowers, 2008  Salinity tolerance in halophytes  New Phytologist  179

Dassanayake & Larkin, 2017 Making Plants Break a Sweat: The structure, function, & evolution of plant Salt glands Frontiers of Plant Science 2017

Flowers & Colmer,  2015 Plant Salt Tolerance: Adaptations in Halophytes   Annals of Botany, February 2015

Flowers et al, 1990   Salt tolerance in the halophytic wild rice, Porteresia coarctata Tateoka  New Phytologist  1990 

Gonzalez, 2019 Adaptation of Halophytes to Different Habitats  DOI: 10.5772/intechopen 87056 link

Gupta, Halophyte Plants Biology Discussion 

Lutts & Lefevre 2015  How can we take advantage of halophyte properties to cope with heavy metal toxicity in salt-affected areas?  Annals of Botany 2015

Nikita, Halophytes: Classification and Characters of Halophytes Biology Discussion

Reddy, Halophytes: Meaning and Types Biology Discussion

Ungar, I. A. & Binet, P., Factors influencing seed dormancy in Spergularia media, Aquatic Botany, 1, 45, 1975.

Ventura & Sagi, 2015 The Development of Halophyte-based agriculture: past & present  Annals of Botany 2015

The post Halophytes: Salt Tolerant Plants appeared first on Lizzie Harper.

In autumn, roses produce hips.  These come in a wide variety of shapes and colours, some showy and some much more discrete.  The basic anatomy of all these varied rosehips is the same.

Rosehips are false fruit

The rosehip is a false fruit, also known as an accessory fruit.  Other synonyms you may have come across include pseudo-fruit and pseudocarp.  (Compound fruit is also used, and can describe both compound and multiple fruits.)  An accessory fruit describes fruits from multiple ovaries which develop in a single fruit.

This means that the fruit (or hip) does indeed contain seeds.  Importantly though, it contains a lot of other tissue too.  The extra tissue does not come from the ovary alone, but from tissue near the carpel.  (A carpel is the female reproductive structure of a flower.  It consists of the ovary, pistil, style and stigma.  These may occur singly, one carpel per pistil; or several carpels may be fused together into one big ovary.  This unit is also known as a pistil.)

The diagram below shows a simplified and basic cross section of a flower.

Roses are not the only plants with false fruit.  Strawberries, pears, apples,  and figs are all considered false fruits.

The extra tissue in a strawberry, pineapple and fig is formed from the receptacle (see the diagram above) which has become swollen as the seeds ripen.  Strawberries carry their fruit on the external surface of the juicy receptacle tissue.  Those little “pips” on a strawberry are actually individual fruits, bearing seed.

In the case of pomes like the rosehip, pear and apple the swollen tissue comes from the hypanthium.

A hypanthium is the area where the base of the calyx, corolla (petals), and stamens come together to form a tube.  This is often cup-like, and can be referred to as a floral cup.  The Rosaceae family (pears, roses, apples) all have these swollen hypanthium.  In the case of the rose, the hypanthium is called a “hip”.  For more on the Rosaceae, check out the Ohio Plants page.

You can easily see the ovary on a rose, it’s the slightly bulging green area below the petals and sepals.  This is the hypanthium and, once ripe, becomes the hip.

Cutting a rosehip in half

When you slice a rosehip down the middle, you see lots of “seeds” and soft flesh.  The outside of the hip is often scarlet or crimson, and the flesh attractive to animals which will eat it and thus disperse its seeds.

At the top of the hip, furthest from the stalk, you can see the remnants of the sepals, stamens and anthers.  You can also see these on an apple, quince (below) or pear; they form the small basal star-like area.

The red fleshy part of a rosehip is actually just a shell, a hypanthium.  Within this, though, lurk the seeds.

Inside the skin of the hypanthium is fleshy tissue,  and areas crammed with seeds.  Each of these seeds is, in fact, not a seed but a fruit, called an achene (for more on achenes check out my blog).  Lots of single fruits or achenes.  Inside each of these, lies a seed.

So to find the seed of a rose you need to travel through the red external skin, through the fleshy tissue, and through the achene wall of a single fruit.  There, at the heart of things, sits your rose seed.

The rosehip is a perfectly designed seed-pod.

An overview of rosehips, and what to look for when you illustrate them

I created a handout explaining this anatomy, and also with a list of things to look at and consider when you do a botanical illustration of a rosehip.  What shape is it?  What colour?  How long is its stem?  Is it shiny? Is the hip solitary or borne in a cluster?

As I said, this is a brief (and slightly brutal) overview of the structure of the rosehip, nature’s perfectly designed seed container.

The post Botanical Illustration: Rosehips appeared first on Lizzie Harper.

This chart of flowers of walks and the wayside shows a wide variety of different flower shapes.  Here’s how we go about naming some of them…

First, we have to accept the amazing variety of form.  So what causes this variety?  Flower shape depends on how the segments of the perianth (sepals and petals) are arranged, and what shape they are.

I need to give a caveat before setting out.  There is an enormous amount of variation between definitions of flower shape.  Different botanists use different terms.  They may choose from only a handful of shape definitions, or from an enormous selection.  Many of the definitions seem to be almost inter-changeable.  I’ve done my best to try and untangle some of these contradictions, but please do get in touch in the comments section if you spot glaring errors!

Flower symmetry

The first thing to consider is the axis of symmetry.  Does the flower have bilateral symmetry?  Does it have a clear top and bottom, with two similar sides?  If you cut it in half would both sides be mirror images?  This is known as Zygomorphic symmetry.  Violets show this form.

If a flower is radially symmetrical, then you can cut it in half anywhere and the halves will be identical.  It’s a little like the idea of cutting a cake into two equal parts.  This is referred to as being Actinomorphic.  Most flowers show this symmetry; cranesbills and daisies, forget-me-nots, roses, and borage flowers.

For more on flower symetry, check out the blog from Orbis Environment.

Early dog violet Viola reichenbachiana with several flowers showing Zygomorphic symmetry

Dog rose Rosa canis showing Actinomorphic symmetry

Flower shapes: How to approach these terms

There’s no pretty way to do this, except by working through each botanical term one by one. Brace yourselves, there are about eighteen of these terms to get through!

Cyanthiform

First up is Cyanthiform.  A Cyanthiform flower is shaped like a cup of a bowl.  It has radial or actinomorphic symmetry.  The petals curve upwards, forming the bowl shape.

Buttercups have Cyanthiform flowers.

Cruciform

Cruciform flowers have four petals, and are cross-like.  They have Actinomorphic symmetry.  Many flowers have this form, although often they’re little white numbers that we might overlook.

the Bedstraw family all have little white Cruciform flowers.

Crateriform

Crateriform flowers are similar in shape to Cyanthiform ones.  To be honest, I couldn’t find any online reference which made any difference between the two clear.  Perhaps it relates to petal number?  Or maybe the terms are inter-changable?

In any case, Crateriform flowers are bowl shaped, rather like a saucer.  They show actinomorphic symmetry.

A good example of a Crateriform flower is the poppy.  In this case, I’m using the California poppy.

California poppy Eschscholzia californica

Coronate

Coronate flowers are easy, it’s rather a relief.  Any flower which is crown-like, and looks like a daffodil is coronate.  I can’t think of many flowers that do take on this form, except for the masses of variety of Narcissus and our spring daffs.

Wild daffodil Narcissus pseudonarcissus

Campanulate

Another easy one.  Campanulate means bell-shaped, or bell-like.  In fact, all the bell flowers are campanulate.  That’s why their family is called the Campanulaceae!  Although they have a longer corolla tube or throat, they’re still radially symmetrical.  Campanulate flowers are actinomorphic.  A good example of a campanulate flower is the harebell

Harebell Campanula rotundifolia

Calceolate

Calceolate flowers are very distinctive, and it’s an uncommon shape.  The term translates from the latin as shoe-like, or slipper-like.  The only examples of calceolate flowers I can think of are the slipper orchids, none of which I’ve illustrated.  Calceolate flowers are bilaterally symmetrical, so they are zygomorphic.

Urceolate

Urceolate flowers are like little urns or vessels, facing down.  They have neat petals at the top and a rounded corolla tube.  They’re actinomorphic.  The heather are a great example of urceolate flowers, especially the bell heather.  Another good example is the blueberry, and the Strawberry tree.

Tubulate

Another self-explanatory term.  Tubulate flowers are like little tubes.  Their petals don’t splay out at the top of the tube.  An example of a tubulate bloom is the Cigar flower.  You may not be surprised to hear I’ve not illustrated this species.

Stellate

Stellate flowers are interesting.  They’re star shaped, and radially symmetrical.  But the most interesting thing about these actinomorphic blooms is that they consist of tepals, not petals.  “What”, I hear you cry “is a tepal!?”  Some flowers have sepals and petals which are so similar as to be almost identical.  In many flowers, the sepals are very different from the flowers, and mostly green.

With stellate flowers such as lilies, the onion family, and tulips this is not so.  The sepals are as brightly coloured as the petals, and are often indistinguishable.  You can only tell them apart by seeing where they attach to the centre of the flower.  It’s easier to refer to both the sepals and the petals as tepals.

Three cornered leek Allium triquetrum

Salverform

Salverform flowers are shaped like a long tube, and have a flattened disc of petals at the top.  There’s not much curving of the petals, so the face of a salverform flower is pretty flat.  Plumbago is the example given by many of my references, but I’ve not illustrated that.

Salverform flowers are antinomorphic, posessing radial symmetry.

Saccate

Yet another of these flower shapes that I’ve not illustrated.  Saccate flowers have their basal coralla area extended and swollen, like a bag.  The corolla is fused into a tube.  The distinctive bulge is always on the lower side of the flower.

Saccate flowers are zygomorphic, or bilaterally symmetrical.  Unfortunately, the only example I could find was the Nemathus.  Alas, it;s another plant I haven’t yet illustrated.

Rotate

Rotate flowers are very common.  However, their distinctive characteristic is that the petals aren’t fused together, or if fused it’s a very short tube. No corolla tubes or fusing.  Clearly, rotate flowers are actinomorphic. Tomato  flowers are rotate.

I’m going to admit to a background level of confusion here.  Different sources have different opinions on what species show a rotate form.  I’m erring on the side of caution, and leaving the tomato as our sample flower.  Unfortunately, it’s another species I’ve not illustrated!

Papilionaceaous

We’re back onto safer ground with a papilionaceous flower form.  These are said to resemble butterflies, hence the name.  They’re zygomorphic as they show bilateral symmetry.  A papilionaceaous flower is easy to spot.  All the vetches and the pea family show this flowering shape.

Bitter vetch Lathyrus linifolius

Ligulate

It’s another easy one to explain.  A ligule is the strap-like petal found on the ray florets of the Compositae.  So a plant having a ligulate flower form is one that resembles a daisy.  Outer ray-like petals are the order of the day.  Ligulate flowers are actinomorphic.

The clearest example of a ligulate flower form is the daisy.

African daisy Gerbera

Labiate and Bilabiate

Labiate flowers have lips, or are lipped.  The flowers look like a throat with an upper an lower lip, resembling a mouth  They tend to have long, fused corolla tubes with an enlarged lower lip.  Labiate flowers show bilateral or zygomorphic symmetry.

Bilabiate flowers have two lips.  These are often fused at their bases.  All the mint family (Lamiaceae) have bilabiate flowers.

There’s rather a good link if you want to know more about labiate flower form, from Orbis consulting.

Catnip Nepeta cataria

Galeate

Galeate flowers are hooded, or helmeted.  Like the labiate flower forms, they have a clear lower lip.  The main distinction is the obvious hood over the top of the flower.  This is called a galea.  Think of a dead nettle or monkshood (the clue’s in the name!).

Lousewort also have a galeate form.

Lousewort Pedicularis sylvatica

In my illustration the hood is less pronounced than it might be.

Funnelform

Another easy one to end with.  Funnelform flowers look a whole lot like a funnel.  The flower shape widens slowly from the base, into a trumpet or funnel shape.  Like many of the other flower shapes, funnelform blooms are actinomorphic.

The most obvious examples of funnelform flowers are the Convulvulus, like the morning glory below.

Morning glory Ipomoea purpurea

Flower shapes: An overview and conclusion

Now we’ve gone through each shape one by one, here they all all together on one sheet:

My main references for this blog were The Cambridge Illustrated Glossary of Botanical Terms by Michael Hickey and Clive King, and Kew Plant Glossary by Henk Beentje.

There are loads of websites on this topic, all with slightly different terms.  A good one is the Flowers on India site, and the Seed site.  It can be useful to have an online dictionary of botanical terms to refer to, the Wikipedia dictionary of botanical terms is pretty exhaustive, and the Florabase glossary is a good resource.

The main thing to bear in mind, as your head spins with the variety of flower shapes, is what it’s all for.  The diversity and beauty of these structures comes down to pollination, and attracting pollinators to a flower.  As Candace Galan states in the article “Why do Flowers vary? “Nearly all botanists give animal pollinators credit for the vast smorgasbord of flower shapes and sizes observed in nature.”  However, as she point out, other environmental factors are also involved, as are a plant’s enemies and the costs of producing these amazing flowers.

For more of my blogs on plant morphology and botanical terms, click the link.

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The author saw a sketchbook study I’d done of this invasive plant online, and got in touch.  He is managing director at Environet a company which eradicates knotweed.  Nic is a specialist in the field, and knows more than seems possible about this plant.

Sketchbook study of the Japanese knotweed Polygonum cuspidatum. For more on this illustration please check out my previous blog.

Deciding what illustrations were needed for the book

I met up with Nic on his boat in London, on a hot summer day.  We discussed his ideas for the book.  Together, we decided what illustrations were needed.  His premise is that the plant is valuable as well as destructive.  Its reputation has as much to do with hysteria and scare-mongering as with botanical truths.  My sort of a story.

There was a need for diagrams as well as botanical illustrations.  Armed with this information, I set off home and began working on pencil roughs.  Many of these were technically complicated, but straight-forward to draw and colour.

Diagrams

Annotated cross section of a leaf (the annotations are mine, they look better in the book!)

There were some that required a little more thought; although the processes of photosynthesis and transpiration have been illustrated many times for text books and online resources, often these illustrations are not very lovely; I wanted to make informative diagrams that were also visually pleasing, and species specific.

Diagram showing the process of Photosynthesis

Diagram showing the process of Transpiration

Illustrating Japanese knotweed: Terrifying reference!

My favourite illustrations were definitely the ones of the plant itself.  I was very taken with the root crown, its little pink shoots and the way it spreads so effectively (this is why it’s so hard to eradicate!)

Root crown of Japanese Knotweed

For a full plant portrait of Japanese knotweed, I (obviously) had to get my hands on a specimen to work from.  It’s not as common round us as in other places, but after making enquiries I managed to track down a clump of it to an area of common land just above the neighbouring village of Clyro.

I was in something of a panic as I worked; knowing that it was vital to dispose of all the parts of the plant carefully once I’d illustrated it.  Knotweed can re-grow from tiny fragments, and as we know, once established it can be really tough to get rid of.

For more on the legal niceties of controlling Japanese Knotweed, take a look at Knotweed Help’s article.

Japanese knotweed Polygonum cuspidatum

Working from life, the flat leaf bases are really clear, and I could really look at what was going on with the form and shape of the tiny white flowers.  In many ways it’s very similar to the Russian vine, Mile-a-minute Polygonum baldschuanica, and the two had me confused until I sorted out the distinctive shape of the leaves.

The problem of possibly bringing this plant into my own garden was solved by keeping everything in a bag as I worked, and by burning it in the wood-burning stove once I was finished.  I did keep an eagle-eye out for unexpected shoots and seedlings for some months afterwards, however…

Japanese knotweed flowers

Another illustration I loved doing was of the flowering spike, or raceme.

Flowers of Japanese knotweed with a range of pollinating insects

This illustration shows what a wide array of insects visit the plant and how it can be good for wildlife.  Pictured alongside the flowers are a bee, ant, and hoverfly.

Illustrations in the book

When I received my copy of the published book, I was really impressed.  What one might have thought of as a dry subject had been wonderfully brought to life by Nic Seal; his knowledge and passion makes the text fascinating, and a joy to read.  The photos that accompany it are excellent, and the book has a well-produced and classy feel to it; it wouldn’t look amiss on a coffee-table.

Publicity photo of the cover of “Japanese Knotweed: Unearthing the Truth” by Nicolas Seal

I would recommend this book to anyone with even a passing interest in this plant.  It’s a project I’m pleased and proud to have worked on.

The post Japanese Knotweed: Botanical illustrations and diagrams appeared first on Lizzie Harper.

Like grasses and rushes, they are monocots, but are a distinctly different group of plants.  Here is a beginners guide to the Sedges.  (For a beginner’s guide to the Grasses, please click here.  For a guide to the rushes follow this link.)

Anatomy of sedges

Anatomy of the Common sedge Carex nigra

Vegetative Features of Sedges

The first and easiest way to spot a sedge is by looking at its stem.  Sedge stems are solid, and unlike grasses, they don’t have nodes or joints.  Sedge stems are triangular in cross-section, three sided, especially towards the base of the stem.  In general they are tough and wiry.

Sedge stem of the Greater tussock sedge Carex paniculata, showing it’s triangular shape.

Leaves are similar to grass leaves, being formed from a blade, a sheath (the hollow tube below the blade that encloses the stem), and a ligule (a membranous flap at the junction of the blade and the sheath).

Leaf shape varies enormously between species.  Some leaves are needle like, some have spikey points, some have hollow tips, some are broad and flat, some have smooth edges while others are toothed, in some species (Like the Deer–sedges) the leaves are reduced to tiny flaps, and in others (like the spike rushes) there are no leaf blades at all, just a sheath.  Colour differences are rife too, from yellows through vivid greens to glaucous, almost blue shades.

Sedge leaf variety

Unlike grasses,  sedge ligules are fused to the base of the leaf blade.  Below is a range of sedge ligules.  As with grasses, these can be used to identify different species.

Variety of different ligules seen in different species of Sedge

Sedge growth habit

Size and growth form varies in sedges, and both are an important way of telling species apart.  The growth patterns relate to the way shoots grow from rhizome (the underground and horizontal stem).

Some will grow in dense tussocks, like the Greater tussock sedge Carex paniculata.  Other tussocky sedges include the Schoenus and Trichophorum species.

Sedge Greater tussock sedge Carex paniculata showing its tussocky growth habit

Other species show different growth patterns from the rhizome, putting up shoots which are close to one another, and which radiate from the centre.  The Few flowered spike rush Eleocharis quinqueflora is a good example of this, as are the Isolepis species.

The Few Flowered Rush Eleocharis quinqueflora

In other sedges, there’s far more space between the shoots coming up from the rhizome, which leads to the plants having a creeping habit.  They’re sometimes referred to as “stoloniferous” which gives a good clue to their growth, even though it’s technically not quite right (unlike the stolons of grasses, rhizomes contain food supplies).  Lots of sedges grow like this, like the Stiff sedge Carex biglowii.

Shoots growing up from along the rhizome; Stiff sedge Carex biglowii

For more on these differences in rhizome growth, consult the bible for sedge enthusiasts, Sedges of the Birtish Isles by Jermy, Simpson, Foley & Porter (p. 5-6) There’s also information on how the rhizome itself can be used to tell species apart, by seeing whether it’s woody or not, and by looking at the leaf scales that grow from it.

Flowers of Sedges

The flowers and fruits of sedges are markedly different to those of grasses.  They take a little getting used to.  As with many areas of botany, they have nomenclature specific to their family.

Sedge flowers are known as Inflorescences.  They are made of lots of smaller florets.  Like grasses, they are wind pollinated.

These florets are grouped together into cylindrical or oval clusters which are known as Spikes or Spikelets.

These spikelets are arranged differently, according to species.  They can be solitary, un-branched and at the tip of a stem.  Or they can be arranged in groups, into branching flowering heads.  There may be bracts below the spikelets.  The form and length of these bracts is important when telling species apart.

Common cottongrass Eriophorum angustifolium has a branched flowering head.

The Few-flowered Spike-rush Eleocharis quinqueflora has solitary spikelets borne at its tips (see picture above).

Bisexual sedge florets

Across the sedge species, each floret is tiny, and grows in the junction between the stem and a tough scale called a glume.  Many sedge florets are bisexual, bearing three stamens (with stiff filaments bearing anthers), stigmas (less feathery than in grasses and varying from 2 to three depending on species), and an ovary inside a covering; this unit is known as the utricle.

Diagram of a bisexual sedge flower

This diagram shows the anatomy of a bisexual sedge flower.  The utricle encloses the ovary (and eventually encloses the fertilized fruit, known as a nutlet) and may have a pointed tip or beak.

The Great fen sedge Cladium mariscum has bisexual flowers and a branching inflorescence.  Bisexual flowers can also be borne in non-branching inflorescences (as in the Black bog rush Schoenus nigricans below)

Bisexual florets on the Black bog rush Schoenus nigricans

Unisexual sedge florets

However, the florets of the Carex (true sedges) and Kobresia (false-sedges) families are unisexual, meaning the male and female flowers are separate.

Diagram of a unisexual male sedge floret

Male flowers have three stamens and a glume.  In male spikelets, the lower male flowers may be sterile and have larger glumes.

Diagram of a unisex female sedge floret

Female florets have a bottle-shaped utricle with a glume below.  In some species there are two stigmas on the utricle (like the Stiff sedge Carex biglowii and the Common sedge Carex nigra) and these tend to mature into a flattened curved nutlet.

Sedge with two stigmas Common sedge Carex nigra

In other species there are three stigmas per utricle (as with the Carnation sedge Carex panacea); these tend to mature into a rounded or somewhat triangular nutlet.

Sedge with 3 stigmas Carnation sedge Carex panacea

Although sedges with unisexual flowers may have only all-male-floret or only all-female-floret spikelets, this isn’t always the case.  In some species the spikelets of both sexes are carried on the same plant, with all the male flowers at the top and female ones at the bottom (androgynous), or vis a versa.

Bottle sedge Carex rostrata has unisex florets and bears thin male spikelets above the female ones, and thus is androgynous.

In the Diocecious sedge Carex dioica, male flowers are carried on one plant with the female spikelets on another (the clue is in the name, I suppose).

Different unisex florets appear on different plants in Diocecious sedge Carex dioica

This arrangement of the tiny spikelets, and whether they’re bisexual, male or female is the bit of sedge anatomy I find most confusing!

Nutlets or fruit of sedges

The fruits or nutlets of sedges are vital when it comes to telling species apart.  Their shape and size matters.  The absence or presence of a beak is important.  Shape of a beak (if present) is vital.  Colour, hairiness (or not), and presence or absence of veins are all important.

diverse selection of sedge fruit or nutlets

Variety

The variety of sedges is amazing.  It includes beautiful species resplendent with white bristles such as the cotton grasses Eleocharis.  Then there are elegant drooping plants like the Pendulous sedge Carex pendulosa and the blueish Glaucous sedge Carex flacca.  Unobstrusive species that resemble rushes like the Black bog rush Schoenus nigricans are lovely, too.  Large plants with toothed leaf blades like the Great fen sedge Cladium mariscum are dramatic representaives.  There are what I think of as “typical” sedges like the Stiff sedge Carex biglowii.  Don’t forget deauties with extraordinary fruit (like the Bottle and Star sedge, Carex rostratum and echinata respectively.)

Below is an array of these fine plants.  I’ve been commissioned to paint these by the Field for School Studies.  They appear on fold-out guides to different habitats.

A small variety of the more than 5,500 species of sedge

Identifying sedges

There are several things to consider when trying to identify a sedge to species level.  Think about how it grows from the rhizome.  Consider leaf width, length and colour.  Lok at leaf ligules.  Where is it growing (habitat)?  What size is the plant? See whether it has separate male and female flowers.  Look for details of the spikelets.

With Carex species, you first and foremost need to consider the nutlet or fruit.

Glumes, at the base of the spikelet, need to be examined and the colour and shape considered.

Bracts (below the spikelet) need a close examination.

Figure out if there are two or three stigmas on the flowers.

Look to see how the flowers are arranged on the plant.  Both their position on the stem and in terms of where female and male flowers sit if relevant.

References

I love sedges, although I readily admit to being almost a total novice when it comes to identifying them in the field.  There are some splendid courses on sedge identification out there (like the Field Studies Council one, which I blogged about attending last year); and for the British Sedge species some very useful books.  These include the “bible” for Uk sedge identification, Sedges of the British Isles by Jermy, Simpson, Foley & Porter.  It’s published by the Botanical Society of the British Isles and is a hefty and very comprehensive volume, complete with a lot of detailed information on growth and anatomy in the opening pages, and distribution maps for each species.

I also find the Colour Identification to the Grasses, Sedges, Rushes and Ferns by Francis Rose very helpful and clear, along with Collins Guide to the Grasses, Sedges, Rushes and Ferns by Fitter, Fitter and Farrer.  The sedge section in Collins Flower Guide by Streeter has some very good illustrations by Christina Hart-Davies.  For a comprehensive if dry resource, look at the Flora of the British Isles by Clapham, Tutin and Moore.

Diagrams in this blog owe a lot to the incredibly helpful The Cambridge Illustrated Glossary of Botanical Terms by Hickey and King .

I do hope that this introduction to the beautiful sedges will have inspired some of you to go out and start looking at these beautiful and frequently overlooked plants.  Along with grasses, and rushes, they’re proving to be really fascinating; both to learn about and to illustrate.

The post Sedges: An introduction appeared first on Lizzie Harper.

(We should also mention the rushes and sedges.  These are also monocots.  For a beginners guide to sedges click here, for a beginners guide to rushes follow this link.)

Drawing a plant is one of the best ways to begin to understand it.  I hope this crash course in grass anatomy will help.

Anatomy of Grass:   Overview of the Plant

Grasses have long leaves or blades, straight thin roots, a rounded (often hollow) stem (or culm), and a flowering spike.  Lots of people may not realise that the top region of a grass plant happens to be the plant’s flowers and seeds.  It becomes obvious when you think about a grass like wheat, but other species might fall under the radar.

Bread wheat Triticum aestivum

The culm of a grass has “knees”, these are known as nodes.  These nodes might be at a bend in the culm, or just on a straight run of the stem.  The culm tends to be swollen at the nodes.  They may be hairy or smooth, depending on species.  This bending at the nodes is known as genticulate growth.  Some people confuse grasses with sedges and rushes; remember that grasses are the only one of these groups which can “bend at the knees”.

The space between these nodes is called the internode.  Its length can help differentiate between species of grass.

Blades (leaves) of grass tend to be flat and linear.  They are rranged alternatively up the culm, and have parallel and unbranching veins.  Blades can be broad, or needle like.  In some species they roll in on themselves to make bristle-like leaves.  Noting if they are hairy or smooth helps determine the species.

The blades of grass grow up the culm like a tube, then grow outward.  This encircling or tubular covering is known as a sheath. Sheaths may cling tight to the culm.  They may be loose and inflated.  This is yet another thing to look out for if you’re trying to i.d. a grass plant.

Overview of the anatomy of a grass (Meadow oat grass Avenula pratensis)

Grass Ligules

Ligules are little flaps of membranous tissue that form at the top of the sheath and the base of the leaf blade.  They are very cool as their shape varies a great deal from species to species.  In many cases they’re tiny, so a hand lens might be handy if you’re going to take a closer look.  Some ligules are pointed, some are rough edged, some very thin, some broad and easy to spot.  Some species have no ligule, or have a ligule which is reduced to a ring of hairs.

Sometimes the edges of the leaf blade cling to the culm and surround the ligule (as in the second illustration below); these structures are called auricles.

Ligule variety in different species of grasses

Inflorescence variety in Grasses

The flowering part of a grass plant is called the panicle, flowering spike, inflorescence or flower-head (many of these terms also apply to other families of plant, and botanists use them somewhat differently at times, which can be confusing). These flowering heads consists of lots of tiny grass flowers which are called spikelets.

Diagram showing flowering spike diversity in the Grasses family: Spreeading panicle, flowering spike, Raceme & Compact panicle

If the flowering spike is unbranched, with each individual spikelet attached to the central stem by a stem (or rachis) it’s known as a raceme (as with Rye grass Lolium perenne and Tor grass Brachypodium pinnatum).

Racemes: Tor grass Brachypodium pinnatum and Italian Rye grass Lolium multiflorum

Panicles often refer to grasses whose spikelets are borne at the end of stalks on a branching flowering head.  They show an enormous amount of variety both in individual plants (depending on the age and developmental stage of the plant), within species, and (obviously) between species.

Variety of panicle shape: Yorkshire Fog Holcus lanatus showing one panicle still within the sheath, one fully spread at maturity.

Some other grass species with spreading panicles include Cocksfoot Dactylis glomerata, Common bent Agrostis capillaris, and Wavy hair grass Deschampsia flexuosa.

Spreading panicles in Cocksfoot Dactylis glomerata, Common bent Agrostis capillaris, and Wavy hair grass Deschampsia flexuosa

Panicles can also be very compact, and look like one tight structure.  This is particularly true of the Meadow foxtail Alopecurus pratensis.

Tight panicle shown by Meadow foxtail Alopecurus pratensis

Some other grasses with tight panicles include Crested Dog’s tail Cynosurus cristatus, Twitch grass Alopecurus myosuroides, and the Foxtails.

Tight panicles shown by Crested Dog’s tail Cynosurus cristatus, Twitch grass Alopecurus myosuroides

Grass Spikelets

Each individual spikelet, or flower, is made of distinct parts.  The stalk of each flower is called the rachis, and flowers are arranged alternately, or in a zig-zag fashion along it.

The base of each spikelet, be it one or several distinct flowers, is held in a pair of glumes.  These paired glumes have distinct upper and lower glumes, and these structures are important in determining grass species.

The glumes may have bristles or spikes attached to them.  These are called awns, and can be long or short, bent or straight, twisted (as with many Oat Avenaspecies), or absent.

Diagram of an individual grass flower or spikelet

Inside the glumes is the floret, which is the stamens and styles of each flower enclosed by two further scales or bracts, the lemma and the palea.  You’re down to hand lens work now, but characteristics to look out for are nerves along the middle (or lack of nerves), awns (or lack of awns), hairiness or not, and colour.

Normally, there are three stamens bearing anthers per spikelet; these often hang out beyond the flower; look closely to find purple ones (Timothy grass and Meadow Foxtail), orange ones (Orange foxtail), white, or cream anthers (many of the Bromes). False oat grass Arrhenatherum elatius has bright yellow stamens.

False oat grass Arrhenatherum elatius with yellow stamens and Meadow Foxtail Alopocerus pratensis with purple ones

Tillers

Some grasses put out lateral shoots, sometimes at quite a distance from the main plant.  These are known as tillers, and grow from horizontal rhizomes, or root-like stems which grow along the ground.  Grasses can rapidly colonise new habitats with this vegetative form of growth.

Tiller and rhizomes, shown on the Rough meadow grass Poa trivialis

Identifying grasses species: Features to look out for

Habit and habitat

What area is the grass growing in?  Is the ground wet or dry?  Calcareous or acidic?  Disturbed?  What season is it?

What shape and height is the plant?  Is it erect, tufted, or droopy?  Likewise, are the panicles tight or drooping, compact or loose, many branched or not?

Does it have rhizomes and tillers?

Leaves

How long and how wide are the leaves?  Are they hairy or smooth? Flat or inrolled and bristle-like? What colour are they?

Ligules

Fold the leaf blade back from the stem and find the ligule.  Look for its size, shape, edge, presence…

Spikelet

How are these arranged on the stem?  How big are they?  What colour? What texture?

Spikelet parts

Compare the size of the 2 glume scales, the number of nerves, awns or not, hairy or not.  Are the palea and lemma  awned or not?  How many nerves do they have?

Spikelets of False oat grass Arrhenatherum elatius and Common Oat grass Avena fatua

If you’re interested in learning more about British and European grasses, there are some really good reference books out there.  The “bible” of grasses is C.E. Hubbard’s Grasses; Colour Identification to the Grasses, Sedges, Rushes and Ferns of the British Isles by Francis Rose, Collins Guide to the Grasses, Sedges, Rushes and Ferns of Britain and Northern Europe by Fitter, Fitter and Farrer. You could also take a look at Collins Flower Guide by Streeter although it’s rather arrogant of me to suggest this as the grasses plates were all completed by me (with a great deal of help from David Streeter!)

I hope you’ll give the grasses a chance, and end up loving them as much as I do,  their beauty and diversity is mind-boggling.

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