Meeting date: 27 July 2016
(Leader: Frances Abraham)
Ten members succeeded in gathering at the eastern corner of Arundel Park at Offham, despite the leader’s half-witted muddling of the grid reference. Entering the Park, we recorded the chalk flora on the banks of the track running NW up the east-facing slope, which included Helianthemum nummularium (Common Rockrose), Thymus polytrichus (Wild Thyme), Asperula cynanchica (Squinancywort) and other species of this habitat. Several species, such as Koeleria macrantha (Crested Hair-grass), had not been recorded previously in this less visited part of the Park in TQ00J. Crossing into TQ00E, we turned into the dry valley which runs down to Swanbourne Lake. On the east-facing slope it was a pleasure to find Thesium humifusum (Bastard-toadflax) where rabbits and sheep had grazed down the sward. Patches of disturbed soil supported numerous plants of Marrubium vulgare (White Horehound).
We picnicked at the western end by Box Copse, overlooking the Lake with its large colonies of Hippuris vulgaris (Mare’s-tail). On the upper slope around Box Copse were species typical of disturbed chalk: Inula conyzae (Ploughman’s-spikenard), Cynoglossum officinale (Hound’s-tongue), Verbascum thapsus (Common Mullein), Atropa belladonna (Deadly Nightshade), Calamintha ascendens (Common Calamint), Lithospermum officinale (Common Gromwell) and more Marrubium. We then followed the path by the Lake out of the Park to Mill Road, stopping to admire Cladium mariscus (Great Fen-sedge) on the shore. Cladium is native in the UK but an introduction to Sussex, where this is its only known site. We wandered back to Offham along Mill Road. The chalky river cliff above the road supports much Buxus sempervirens (Box) in what may be one of its few native sites in Sussex. Rubia peregrina (Wild Madder) scrambles over scrub, and a few plants of Arum italicum ssp. neglectum were seen. We turned off into the car park of the Black Rabbit pub to inspect a fine specimen of Verbascum lychnitis (White Mullein). There were also several plants of V. thapsus, plus a possible hybrid. V. lychnitis is yet another species of disturbed chalk, usually found where woodland has been cleared recently or trees have fallen: here, work on the car park had done the trick.
See also: Penfold, F. “Marrubium in Arundel Park.” Sussex Botanical Recording Society Newsletter, no. 51 (Jan 2001)