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HOW RARE IS THIS WAX-CAP?
Hygrocybe calyptraeformis (B. & Br) Fay
This unique toadstool is listed as Vulnerable in Bruce Ing's "Provisional Red Data List of
British Fungi". This means that it is likely to become endangered in the near future if the
causal agent of its decline is not reduced. This agent is the loss of its habitat, namely,
unimproved grassland. A true estimate of its rarity could be obtained by people reading
this article examining their local churchyards during October and November and sending
any sightings to me. I have already found it in Little Leighs Churchyard in 1993 and
1994 and Graham Smith has found it in Fryerning Churchyard.
It is unmistakable and does not require microscopic examination. Rosy-pink to lilac in
colour, with a pixie-cap up to six centimetres across, opening out and splitting radially
when older. Like all wax-caps the gills are relatively thick and waxy. The stipe is lighter
in colour and the whole fungus easily breaks up when handled.
Your observations if sent to Tony Boniface, 40 Pentland Avenue, Chelmsford, Essex,
CM1 4AZ could establish its present situation in the Essex countryside.
Tony Boniface
AN ASPEN PUZZLE
For very many years I have been puzzled by the occasional stand of tall straight Aspen in
a woodland setting, up to 20 metres high. The typical woodland population in my area is
on de-calcified boulder clay the drainage of which, is such, that the watertable can be
expected to be quite close to the surface in winter and often has clumps of Rough stalked
meadow grass growing underneath. The soil does not give the impression of being
infertile, but the typical tree is a very poor specimen probably no more than 6 metres high,
the top branches more horizontal than upright.
The literature I have consulted, as well as personal observation, suggests woodland
clumps are all identical, the same genetic stock from the same original tree on that site
which have arisen from the ever present but often overlooked network of underground
roots. When the woodland is coppiced the cut stumps seem not to grow again, instead the
underground network produces many shoots which grow to shoulder height in the first
year with great vigour but which usually gives a poor low tree.
Aspen seldom germinate from seed because a very moist environment is needed as soon
as the seed drops and then for the remainder of the growing season. Clumps of Aspen,
which are usually very dominant over a small area are invariably of the same sex. This
makes an origin from germination unlikely this would result in a mixed population. I
have heard of the occasional single tree in a woodland setting, which is straight and tall
which I have to accept is because of a dominantly competitive environment. I started to
look at Aspen growing in the shade of other trees and often found the Aspen being forced
away to an angle of perhaps 45° with the top branches reaching perhaps to the ground.
The answer seems to lie in an area of some size being recently coppiced, of
predominantly Aspen facing approximately north, shaded by large dominant uncut frees.
As a young tree Aspen is very vigorous and very soon outstrips its neighbours,
competition is no longer present so upward growth ceases while the adjacent trees catch