A guide to chalk downland species: From plants to reptiles

Chalk grassland – also known as chalk downland or lowland calcareous grassland – is an increasingly rare habitat and one of the richest in Western Europe. In England, it’s mostly found on the North Downs but there are also patches scattered along the East Kent coast.

Kent Wildlife Trust · A guide to chalk downland species: From plants to reptiles

If you’ve ever been lucky enough to visit one of these places, you’ll know just how special the habitat is. So special, in fact, that ancient chalk downlands have been likened to rainforests for their bioabundance and diversity – which is arguably unmatched in the UK.

Despite this, chalk downland is a significantly threatened habitat, and we’ve lost most of it in recent history due to the impacts of fragmentation, the intensification of development and agriculture, species loss, and the domination of coarse scrub that often follows. Traditionally, chalk downlands would have been grazed by wild rabbits and sheep that ate scrub and longer grasses, making way for rarer plants and insects.

Now, conservation efforts are being made to protect and restore the remaining chalk downland areas. With the right management, they can be brought back to their former glory – think of Polhill Bank Nature Reserve, which is now once again home to rich wildflower meadow since we acquired it several years ago.

If you’re looking to get out and about in a chalk downland and want to know what to look out for, or you’re just curious about what makes them so special, we’ve compiled a list of some of the species they harbour.

Use the contents index below if you're interested in any specific class - or scroll at your leisure!

Plants

The yellow and brown flowers of kidney vetch.

The pod-like yellow flowers of birds-foot trefoil

Carline thistle, with its thistle-like centre and white petals.

Common milkwort, with dark purple flowers and long thin leaves.

The small, dense clusters of yellow flowers on lady's bedstraw.

Viper's bugloss with its bell-like purple flowers and protruding red stamens.

Salad burnet, a small green cluster with pink-brown flowers.

Click on the images above to find out the name of each species. You can also click on most of the species names in the table below to learn more about it.

You’ll typically see a wealth of wildflowers, scrub, and bushes at healthy chalk downlands. As for wildflowers, you can look out for:

Species	Habitat	Appearance	Attracts
Fairy flax	Specialised chalk grassland plant.	Its small, white flowers bloom on wiry stems.	Loved by pollinators.
Horseshoe vetch	Specialised chalk grassland plant.	A scrambling herbaceous plant in the pea family with yellow flowers.	The muse of the Adonis blue butterfly.
Round-headed rampion	Specialised chalk grassland plant.	A plant in the bellflower family with purple clustered horn-like buds.	Supports many bees and butterflies.
Birds-foot trefoil	Frequently found in calcareous grassland.	Another plant in the pea family with yellow, pod-like flowers.	Favoured by bees.
Carline thistle	Frequently found in calcareous grassland.	Unique, distinctive plants that resemble seeded thistles with their brown/golden heads.	A nectar source for a wide variety of butterflies.
Milkwort	Frequently found in calcareous grassland.	A low-growing herbaceous perennial plant with blue, pink, or white flowers.
Cowslip	Frequently found in calcareous grassland.	A fragrant, drooping yellow flower in the primrose family.	An important food source for many species of insects and birds.
Salad burnet	Frequently found in calcareous grassland.	A low-growing herb with reddish flower heads and leaves that smell like cucumber.	Loved by pollinators.
Lady’s bedstraw	Frequently found in calcareous grassland.	A plant with dense froths of small yellow flowers and a sweet scent.	Attracts butterflies, bees, and hawk moths.
Viper’s bugloss	Frequently found in calcareous grassland.	A hairy plant with purple flowers and protruding red stamens.	Bees, hoverflies, and butterflies all enjoy them.
Field scabious	Frequently found in calcareous grassland.	A tall herbaceous perennial plant with delicate clusters of lilac pin-cushion flowers.	Hoverflies, bumblebees, and peacock butterflies especially love it.
Marjoram	Frequently found in calcareous grassland.	A perennial herb with clusters of purple and pink flowers.	Loved by ladybirds, hummingbirds, and green lacewings.

Two of the rarer or perhaps more intriguing types of plant found on chalk downlands, though, include dodder and various orchids.

Dodder

Common dodder is quite rare (despite the name) but easy to spot. It’s characterised by its parasitic vine of reddish threads that grow over other plants for sustenance.

The bee orchid, which looks like a bee with purple wings. — © Neil Aldridge

Orchids

All kinds of orchids thrive in the thin, chalky soil of calcareous downlands. Most commonly, you will see the common spotted, fragrant, and pyramidal orchids. Rarer are the musk, bee, man, autumn lady’s tresses, burnt, and early spider orchids.

Scrub and bushes

Typical chalk grasslands are dominated by wildflowers and grasses as you may imagine. Clusters of shrubs and bushes are dotted around healthy sites – but sometimes take over when left ungrazed and unmanaged.

Scattered bushes may include red-berried hawthorn, guelder rose, dogwood (occasionally white-berried), and the purple-berried blackthorn and juniper as a low-growing shrub. Hawthorn and blackthorn provide shelter, nesting habitat, and berries for birds, as well as nectar for pollinators!

Insects

Feeding on and pollinating all those wonderful plants are a huge variety of butterflies, moths, and more. In the chalky undergrowth and crawling amongst the grasses are crickets, beetles, and bees galore. Let’s take a look...

Butterflies

Because of the density of wildflowers, you’ll see quite a range of different butterflies at healthy chalk grassland sites. In fact, nearly a third of all British butterflies can be found in these habitats. Just a few include:

Adonis blue

The adonis blue – the butterfly in our logo – is one of the most characteristic butterflies of chalk grassland. The males have bright blue wings, while the females are a more conspicuous brown. Both sexes share the distinctive white fringes around their wings, framed by black lines.

The adonis blue overwinters as a caterpillar (green with yellow stripes) and feeds on horseshoe vetch, before emerging at the end of summer.

During its time as a chrysallis, it has a special relationship with ants, which bury it in chambers connected to the ant’s nest so they can feed on its sugary secretions! In return, the ants protect it from parasites until it’s ready to emerge.

Because it only feeds on horseshoe vetch, the loss of chalk grassland habitats poses a threat to the adonis blue.

Duke of Burgundy

The small and striking Duke of Burgundy butterfly has brown wings with stained-glass-like orange panels. Its eggs are typically laid under the leaves of cowslip or primrose and, like the adonis blue, it overwinters as a chrysallis – until the following spring.

It is listed as a high conservation priority with a ‘threatened’ status, with a rapid population decline of 35.1% since monitoring began in 1975. They’re only found in a handful of places across England, with chalk grassland being one of their preferred habitats.

A silver-spotted skipper with a fluffy body and brown-yellow wings perched on a marjoram flower. — © Jim Higham

Silver spotted skipper & grizzled skipper

Both skippers are characteristic of chalk downland and are both rare, having been forced into smaller and smaller areas of the UK.

The silver spotted has a green-ish underwing and orange-to-brown gradient on the upper, while the grizzled is brown with white splotches and a thick fluffy body.

The best time to see either species is early in the morning when they bask in the sun to warm up – otherwise, their fast flight makes them rather hard to spot!

Moths

As for moths, chalk grasslands are known for:

Bordered gothic
Pale shining brown
Four-spotted
Chalk carpet

A rarer species that was close to extinction in 1995 is the black-veined moth – an almost entirely white moth with, you guessed it, black veins running through its wings. It feeds on marjoram, birds-foot trefoil, and other herbs.

Crickets and beetles

All the usual critters can be found in this habitat: ants, ground beetles, grasshoppers, and the like. The bloody-nosed beetle, in particular, can be seen with their bead-like antenna, feeding on lady’s bedstraw. They deploy a bright red defensive secretion if attacked – hence the name.

A bloody-nosed beetle with matte black body and bead-like antenna climbing up a stem. — © Tom Hibbert

Wart-biter bush cricket

The wart-biter bush cricket takes its name from its purported ability to bite off warts in early cosmetic procedures! Now, it’s considered one of Britain’s most endangered species and is confined to just 6 sites in England. They need a mosaic habitat of both short and tall tussocky grassland, and lay their eggs singly in bare soil.

You might spot them on a sunny day, but you’d be more likely to hear them stridulating!

Hazel pot beetle

The hazel pot beetle is a lovely bulbous beetle with a black thorax-covering and red wings – they could be mistaken from afar for ladybirds. It belongs to the leaf beetle family and is named as such because of the protective shell-like ‘pot’ that its larvae live in.

They’ve suffered dramatic declines in the UK and are now classified as rare.

Bees and hoverflies

Of course, with any wildflower-rich habitat comes a variety of bees and hoverflies that play a pollination role in the ecosystem.

Some special species include:

Phantom hoverfly
Red-tailed mason bee
Blue carpenter bee
Downland furrow bee
Shrill carder bee

The potter flower bee, a solitary digger species, is considered one of England’s rarest bees, now confined to just a few sites along the southern coast. It has a unique nesting behaviour whereby it uses mud to build pot-like nests for its eggs. It’s also unique in its food preference, opting for plants like viper’s bugloss for nectar!

Birds

Two skylarks fighting in a grey sky. — © Luke Massey/2020VISION

Despite the lack of trees and foliage we typically think of as suited to birds, a few species reside in and rely on chalk grassland. Most often, you will spot ground-nesting birds like skylarks, but you might also see woodpeckers and linnets, particularly if there are scrubs or wooded areas nearby.

The presence of ground-nesting birds is one of the reasons to be cautious when visiting chalk downland sites. It’s easy enough to simply not see their well-hidden eggs and tread onto them, so be sure to walk carefully and keep to pathways with dogs on leads.

Mammals

Konik grazing chalk grassland at Nemo Down, photo by Barry Cook

Mammals like sheep, horses, goats, and cows once played a key role in the delicate ecosystems of lowland calcareous grasslands. Their trampling and grazing behaviours turned the soil and trimmed back domineering plants, making space for a richer variety of species – including rare ones.

Today, most grazers are long-gone from wild spaces, but some conservation groups are reintroducing them as a nature-based solution to restore and protect chalk downland habitats. Kent Wildlife Trust are one such group, and we’re hoping to do exactly that at a proposed reserve we are looking to buy, opposite Polhill Bank in Sevenoaks.

Reptiles

A brown viviparous lizard basking on a lichen-covered rock. — © Danny Green/2020VISION

Finally, no list of chalk downland species would be complete without a firm nod to the many reptiles that reside there.

Adder and viviparous lizards are frequently found basking on warm ground in areas with shorter vegetation, but they also rely on the nearby cover of shrubs and tall grasses to hide from predators.

Invest in the future of chalk downlands

Intrigued by the history of chalk downlands and the species that currently rely on them? Us too. We want to see a future where chalk downland habitats are protected, restored, and more joined-up – so that wildlife can thrive there.

Polhill Bank Nature Reserve was once arable land which we have since restored - with the help of our supporters - to stunning wildflower meadow. Through ongoing conservation work, we hope to see it transformed into rare, species-rich chalk grassland.

As of 2024, we have an exciting opportunity to extend and connect nearby habitats by purchasing additional land, including 26 acres just across the road from the existing reserve. But we can’t do it alone.

Can you support us so we can Protect Polhill?

A guide to chalk downland species: From plants to reptiles

Kent Wildlife Trust

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