Meadow flowers are probably at their very best in June. If you revisit them over the months you can see how the meadows change colour from the yellow and white of buttercups and lesser stitchwort (April and May), to the pinks, light browns and blues of orchids, grasses and speedwells (May and June) followed by the purples and red-browns of knapweed and sorrel in high summer. When Darwin moved to Down House some of the fields in the Downe Valley were sown with sainfoin, a member of the pea and bean family cultivated because the nodules in its roots contain a bacteria which changes nitrogen in the air to nitrate in the soil, making the soil more fertile for growing crops. He wrote, in June 1843:
"The sainfoin fields are now of the most beautiful pink, & from the number of Hive Bees frequenting them the humming noise is quite extraordinary. This humming is rather deeper than the humming overhead which has been continuous and loud during all the last hot days…….The labourers here say it is made of 'air-bees’ & one man seeing a wild bee in a flower, different from the Hive kind, remarked ‘that no doubt is a 'air-bee', - This noise is considered as a sign of settled fair weather."
Amongst the meadow flowers Darwin studied was field scabious. He wrote:
"It has been shown by H. Müller that this species exists in Germany under an hermaphrodite and female form. In my neighbourhood (Kent) the female plants do not nearly equal in number the hermaphrodites."
The great variety of wild plants within the nominated World Heritage Site provide food and shelter for many invertebrates, some of which are shown in the photographs on this page taken at Downe Bank by Grant Hazlehurst, a local entomologist.
Darwin is thought to have been writing about Downe Bank when he wrote at the end of The Origin of Species:
"It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have all been produced by laws acting around us."
To learn more about some of the plants and animals living at Kent Wildlife Trust’s Downe Bank Nature Reserve, join the wardens and assistant wardens, at the open day of this beautiful reserve where Darwin studied plants and picniced with his family. To find out more about open days at Downe Bank, contact Kent Wildlife Trust on 01622 662012 or visit their website at www.kentwildlife.org.uk
Like the bees and wasps whose colouring they mimic, hoverflies are important plant pollinators. Darwin wrote of the long-tongued hoverfly (Rhingia rostrata) that it visited ' flowers of the same species with almost as much regularity as do bees... and when captured they are found covered with pollen'. He also observed that this hoverfly species most frequently visited flowers of pink campion, bush vetch and bugle.
There are 65 species of click beetle in Britain: the photo below shows a click beetle at Downe Bank and is a species likely to have been seen here by Darwin. These beetles get their name from the noise they make when they flick themselves over onto their backs and then spring into the air to escape from predators. They can jump about 30 cms into the air, sometimes somersaulting several times. This is made possible because when lying on its back a click beetle can arch its body under great tension which when suddenly released flicks it into the air. The young of these beetles are larvae known as wireworms, and may live in the soil for up to 5 years, eating plant roots.
Sloe Shield Bug
Look for some of the different species of shield bug feeding on vegetation in the Site this month. They can be easily recognized by their shield-like shape and are sometimes known as 'stink bugs' because many are able to eject an unpleasant smelling liquid when threatened, to frighten away predators. Most of them feed on fruits and leaves, having a long mouth part adapted to pierce and suck plant sap or fruit. At this time of year the adults are mating and laying eggs which hatch about a month later. The young, known as nymphs, look similar to the adults but are wingless and generally have a rounder shape. They shed their skins 5 times before emerging as adults in September. In some species the colour of the adult and/or nymph can vary with age. Adults hibernate during the winter.
On warm sunny days lizards bask in the sun to warm up and catch some of the many insects which live in the grassland.