Four
members met at the Fairholmes car-park on one of the few sunny days
in September to enjoy a mild ramble across the Derwent Reservoir
towards Dovestones Clough and Mill Brook on the eastern side of the
water. As well as appreciating the botanical bounty of the many
Raspberry and Blackberry plants lining our path, we also took the
time to identify many plants, many of which had finishing flowering
and so were tackled vegetatively.
Several plant groups were looked at
in detail, including the Vetches (Vicia
species). In particular, we compared the presence of extra-floral
nectaries on the stipules of Bush Vetch with their absence on Tufted
Vetch. Nectaries outside of flowers are not uncommon amongst plants,
in fact, they seem to have evolved on numerous occasions; for
example, the common fern Bracken also has them. Their function is
seemingly to attract ants that, in turn, will attack insect
herbivores, providing a benefit to the plant. Interestingly, some research has found this effect to be weak, and scientists have
suggested that some plant herbivores may have themselves evolved to
overcome this ant-protection system!
After this overlap between plant
identification and plant-animal mutualisms, we progressed up a sunken
lane with a typical acid grassland flora at head-height, for easy
inspection. We were able to pick out all of the common acid grassland
grasses, including Heath-grass (Danthonia
decumbens),
a handsome grass with large florets that make it relatively easy to
spot, even though it is often at low abundance within the sward. This
is also one of only three native British grasses with a ring of hairs
at the junction of the leaf-sheath and blade, making confirmation
relatively straightforward (for a grass!) Finally, we arrived at the
junction of Mill Brook and Dovestones Clough, where a number of
typical plants of upland streams and acid-neutral flushes were found
and enjoyed. Lemon-scented Fern, Star Sedge, and Creeping
Forget-me-not were all identified and enjoyed.
Botanists wanting to
find out more about the cloughs around the Derwent Reservoirs are
strongly recommended to purchase a copy of Sorby
Record
No. 40 (see the Sorby website), featuring John and Valerie
Middleton's thorough survey of these splendid and exciting
landscapes.
