The Edge of the A303

Wayside and Woodland Flora

David Beeson

5^th May, 2020.

Sunshine and showers are designed to make plants grow. Add a touch of nutrients (Nitrates, phosphates and potassium salts – NPK) and a well-structured soil and they romp away. However, local soils are not the best and only the worst are bad enough to be left for natural plantings. The UK’s best soils (often in East Anglia) are grade 1, those on the edge of the A303 must be grade four million. The banks are pure chalk and fifty years has hardly allowed them to grow any soil on their surface.

You’ll already know that soil is a combination of broken rock particles, plus some decaying organic materials (such as leaves, bark or dead organisms), water and living organisms. The crucial aspects being the combination of particle sizes* and organic material (humus). Water is seldom lacking for long in the UK.

(*too big gives too much drainage, too small stops air and water passage and the particles often clump together – clay.)

As the A3093 merges with the A303 there is a nice parking spot beneath the A303 on the westward side. From there it is safe to wander the road verge … but watch out for idiot drivers.

Ideally, the verge should be cut just once a year – in autumn. This never happens. Most years it is cut in June, killing off many rarer plants, or this year in April – which is not perfect either (but better than June!).

The flat verge and the woodland above hide several beautiful, but small, orchids. Today there are white helleborines in flower. These are often best found under beech trees, yet here they are spreading from the woodland onto the verge on both sides of the road.

These plants are a slow grower, taking at least eight years to develop from seed and then the flowering can occur two or three years after that. This species produces a beautiful white flower that does not open fully, so the yellow lip is often not seen. It can grow up to 60cm in height and can have up to 16 flowers on each stem. It is commonly found in South-east England and south east Wales but is in decline due to a loss of habitat. Woodland Trust.

If you seek out this gem you’ll be in a very exclusive club. Almost no one sees this plant.

Orchid seed is very light and is carried great distances by the wind. Sometimes across from France.

Unlike the slopes, the verge and woodland above have developed a modest soil that supports a diversity of plants that are characteristic of chalk downland habitats. (To see these habitats locally visit one of the ancient hillforts or Broughton Down.)

Almost opposite to this site is a minor road leading south. By parking near the farm and following the footpath / farm track you will enter the southern part of Harewood Forest. As the track enters the woodland you may decide to divert right, along the edge of the woodland. You’ll shortly encounter the remains of a once active badger sett in amongst a hazel and bluebell coppice. Nearby has been a colony of early purple orchids which has been destroyed by tree harvesting some years back.