Nature Reserves

Palmer's Bank
Managed by:	Plantlife International
OS grid reference:	SP 380 173
Nearest postcode	OX29 8DR
Usual work:	Scrub clearance

Palmer's Bank is a small grassy hedgebank beside a field used for arable crops that is home to one of Britain's rarest wild plant, the perfoliate pennycress (Thlaspi perfoliatum), which is a species of national nature conservation priority. The perfoliate pennycress has small greyish-green waxy leaves and a cluster of white 4-petalled flowers. The upper pointed leaves have no stalk, which leads to the appearance that the flower stems perforate the leaves, hence the name. In Britain this threatened species is mainly found within the Cotswold Hills in Gloucestershire and Oxfordshire, and is therefore often referred to as the Cotswold pennycress.

Between 2000 and 2006, not more than 28 plants were recorded at Palmer's Bank in a single year. In 2006 OCV came to the rescue and, with Plantlife International and the support of Blenheim Estate, removed about 10m of the coarse grasses that had smothered the ground. In Spring 2007, when the Ashmolean Rare Plants Group returned to the site, they were amazed to see 95 flowering perfoliate pennycress plants. OCV have continued to help keep invasive fauna at bay in order to aid the survival of this rare flower.

Geology

The perfoliate pennycress thrives on the nutrient deprived rocky areas or grassland on thin soil. The limestone grassland at Palmer's Bank is an ideal habitat for this species.

Conservation Management

Plantlife International is working with the farmer and landowner of Palmer's Bank in order to establish conservation headlands aimed to protect the perfoliate pennycress from extinction. This is important to ensure that pesticides will not inadvertently harm the survival of this flower. OCV assist in retaining this important habitat by removal of the coarse grass that will otherwise smother the perfoliate pennycress and prevent seeds from successfully germinating at the site.