Holm Oak

General Description

By the late 1980s, the Holm Oak was threatening to take over the best of the species-rich chalk grassland. Although cattle reintroduced to graze the grassland do eat holm oak, they have failed to halt the colonisation by new seedlings which thrive in the chalky soils and favourable maritime climate. Regrowth of cut stumps was also a problem despite the use of herbicide.

The solution came about after seeing a documentary on a wood pasture system in the Spanish region of Extremadura which showed how goats had originally shaped those particular landscapes. Inspired by this, and after we researched the feasibility, we introduced a breeding herd of feral goats to an area of the Ventnor downs. They had the immediate effect of controlling all regrowth and seedlings. After a period of thirteen years, the presence of the goats has brought holm oak colonisation to a controllable level with only mature trees free from the effect of goat damage.

We are now going to deal with the mature trees in a different way. In the past, we have clear felled large areas of mature trees which has led to large bare areas that have been slow to re-colonise with chalk grassland but quick to be colonised by weeds. As a result, we are planning to develop a wood pasture system by thinning mature trees. This will allow light onto the ground where chalk flora (and in some cases heathland) will develop. This will be sustained by cattle grazing (or other grazing animals) and the goats will continue to control the growth of woody species by browsing. The whole system will be dynamic.

The project was funded from a Leonardo da Vinci grant.