Worcestershire Record No. 4 May 1998 p. 9

THE ACID FLOWERS

It ought be the name of a rock band, but Worcestershire's "Acid Flowers" are much more self-effacing. We're still finding them, tucked away in the folds of the countryside around Kidderminster where the new red sandstone runs just below the surface, or the Bunter pebble beds blunt the farmers' harrows. These are a select company of plants which favour the light sandy soils in the north, but which have received very little attention from conservationists. This could be because many of them are annuals and very small annuals at that. They also tend to bloom very early in the year, sprouting , blooming, seeding and dying in the space of a few months to capitalise on the limited moisture that their habitat holds in winter and spring. By the time the midsummer sun has loosened the sand grains around their roots, the next generation's seeds are already sown, waiting for autumn rains to trigger germination.

The acid-loving annuals are thermophilous too...they love spring heat and flourish where early sun warms the soil. And that means they can't tolerate competition from grasses or any tall vegetation. It follows that the best sites are south-facing, on a slope which can't be ploughed or isn't worth re-seeding and where the turf is short. It's surprising how many grasslands in north Worcestershire fit the bill and how tiny they can be. In Wilden Lane near Hartlebury Common there are some superb garden lawns, too steep for even a Flymo, which have an amazing collection of acid plants. By contrast, there are still large hillsides as, for example, at Deansford and Churchill, where the flora probably hasn't changed for a century or more, though rabbits have come and gone....and come back again!

Rabbits are the final ingredient, because they keep down the competing vegetation. Sheep do the same job, only with less discrimination, and horses take the huge bunches of false oat and cocksfoot grass which spell doom to delicate annuals.....good conservation tools, horses!

So, what do these diminutive early-flowerers look like? Some are very small indeed, like the Whitlow-grass (Erophila verna) which frosts the ground in some places. It's normally no more than 5cm high and begins blooming in February , not only in sandy fields, but on walltops and road verges too. This is a critical group of plants..the commonest in Worcestershire is ssp verna, but the hairy Erophila majuscula grows in one field at Churchill and is probably overlooked.

With Erophila you often find two species of forget-me-not. The commoner is the Changing Forget-me-not (Myosotis discolor) which has creamy-yellow buds opening into blue flowers. It's still fairly common in many fields and is an indicator that rarer plants might be in the offing. One of these is its relative the Early Forget-me-not (Myosotis ramosissima) which flowers from late March and has tiny, but intensely blue flowers which don't change colour. Recently it shows ferroviatic tendencies, swapping its loyalties from fields to railway banks and can sometimes be found on dry, sunny sidings where the grass is short or absent.

Without exception every acid pasture worth checking has one species which I've come to regard as my "indicator plant". This is the Small Mouse-ear (Cerastium semidecandrum) ,an annual which flowers from late March to May. It likes bare ground, especially around rabbit burrows and is safe from them because it's hairy strap-shaped leaves are flush to the ground and very small! Early on it can be hard to tell from the Common Mouse-ear (Cerastium fontanum) which is perennial and has non-flowering vegetative shoots. In bloom, Small Mouse-ear is obvious because its white petals are much shorter than their enclosing sepals.....these sepals have a transparent border which is very distinctive.

Another speciality with a common "look-alike" is the Lesser Chickweed (Stellaria pallida). You need to look for this on gravelly or sandy soils where there is little or no competition..and you need to look early! In 1998 I found plants in bloom on February 1st, though "bloom" is an extravagant word for a plant with no petals...the flower is little more than a green seed-capsule fringed by up to three stamens. however, the overall appearance often gives this chickweed away. It's a light yellow-green in colour and produces large mats of foliage, often under conifers in gardens. Beware apetalous forms of Common Chickweed (Stellaria media) which usually has larger, darker green leaves and from three to eight stamens. Along with many other acid-loving plants, Lesser Chickweed has taken to roadsides and shares central reservations in Kidderminster with Small Mouse-ear and Buck's-horn Plantain (Plantago coronopus).

Two members of the pea family excel on sand. Bird's-foot (Ornithopus perpusillus) is a delicate grey-green annual with tiny white flowers and is common in north Worcestershire though rare or absent in the south. It is often one of the earliest colonists of sand quarries or building sites and can produce several generations in a season.

Spring Vetch (Vicia lathyroides) is a real blue-riband plant on the sandstone and finding it is worth hours bent double in an April gale, scouring the turf for signs of its dull purple flowers. Its traditional sites were always in the Hartlebury Common area, but Amphlett & Rea also gave it as occurring in "sandy fields east of Kidderminster" in the mid 1800s. On checking these out for the Worcestershire Flora Project, I found that there are at least eight sites in the Kidderminster area, including one of thousands at Deansford, and others at Ismere, Wilden and Habberley. These are important populations of a plant which is very local in Britain and which is rare in the Midlands. The only cautionary note I would offer is to avoid mistaking Spring Vetch for Common Vetch (Vicia sativa) which has larger, brighter flowers....Spring vetch blooms are very small and quietly purple. Occasionally you can find fields which have all these plants.

Then it's time to start looking for the real specialities such as Field Pansy (Viola tricolor) which still flowers on a scrambling course at Wilden. There are special perennials too. Hoary Cinquefoil (Potentilla argentea) is still surprising us on sandy banks in several parts of the county, though mainly in the north, and there must Be more to discover. And, if you'd like a challenge - what about finding a new site for Subterranean Clover (Trifolium subterraneum) which hugs the ground on one horse-cropped bank at Habberley?

The challenge is there......so go sand-seeking this summer!

References: