Butterfly Area – Yew Hill

Yew Hill Butterfly Reserve – by Ivan Arnold

Yew Hill Butterfly Reserve  consists of two hectares of a rare and declining environment, ancient chalk downland. Theland is owned by Oliver’s Battery Ltd (a private propertydevelopment company based in Hove, East Sussex),
who also own the large open field to the south east of the settlement boundary.

It is not a hill fort and the valleys within it are believed tobe tracks used and worn down by centuries to accessWinchester. Footpaths from Oliver’s Battery lead to it, the easiest access being from the end of Plovers Down
or the bottom of Old Kennels Lane. The Reserve has recently been extended westwards through leasing an adjoining 3.6 hectare block of
semi-improved grassland, but this does not have open access.
The site is one of three managed by Butterfly Conservation, Magdalen Hill Down, Bentley Station Meadow and Yew Hill, the smallest. It is good quality
habitat and is important in linking the wider environment, in particular St Catherine’s and Magdalen Hill Down. Butterfly Conservation has been managing Yew Hill since 1991. As far as possible, management is by
traditional means of grazing cattle and sheep. Rare breeds are used as they will eat coarser grasses and plants. Working parties in winter are needed to cut back yew from the boundaries (poisonous to cattle) and to control self-seeding trees, brambles, old man’s beard (wild clematis) and dogwood.
All three of the last named appear more rampant than in the past, the suspect being mild damp winters. In summer ragwort is pulled as it can cause problems with stock.

As a result, orchids and a host of butterfly-nectaring and caterpillar food plants abound, as do numerous mounds made by ants, which enjoy sugary excretions from both the caterpillar and the chrysalis of the Chalk Hill Blue, and in return offer protection.

Up to 35 species of butterfly may be seen at Yew Hill. Noteworthy species include the Chalk Hill Blue previously mentioned, Common Blue and Dark
Green Fritillary and large colonies of Meadow Brown, Gatekeeper and Marbled White. The habitat also encourages moths and other insect life. The small
trees left in parts on the Reserve and the trees and hedges surrounding it are attractive to bird life, and amongst others the Yellowhammer is a yearly visitor.
Butterfly Conservation arranges for volunteers to visit the site each week (and many other areas) from April to September to record the butterflies seen. In this way, a detailed count is built up over time. This, together with weather records, enables trends to be compared across Hampshire and elsewhere and reasons explored for changes to butterfly populations.

Look at Plants of the Month to see flora in this rich habitat.