The 2003 AGM address. Veteran trees and saproxylic invertebrates at Hylands Park
Grifola frondosa and the edible species Fistulina hepatica and Laetiporous sulphureus. Fistulina
(Beef-steak Fungus) causes red-rot in Oak, which is important for beetles such as the rare
Pseudocistela ceramboides, so far known from only one tree at Hylands. It is likely that standard
trees do not harbour such a good saproxylic beetle fauna as pollard trees. However, rot-holes,
shattered branch ends from storms, much dead wood where whole branches have split off from the
trunk, rarely sap-runs, red and white-rot, plus dead branches high up in the tree (home to species
such as Scolytus intricatus) mean that standard Oaks at Hylands do have the potential to provide at
least some sort of habitat for saproxylic species.
Trees Other Than Oak
Of the other tree species in the park, the most important for saproxylic species is probably the
Horse Chestnut Aesculus hippocastanum which was obviously widely planted in the 19th century
(and possibly earlier). This species is a good example of how a non-native tree can become a good
site for invertebrates, providing many of the niches that would normally be found only in much
older native trees. The large pollard tree near the western end of the Seipentine Lake (girth 18ft
6.5ins- 5.65 m) is on part of the estate acquired by Cornelius Kortright after 1797, so the tree was
probably planted some 200 years ago (Horse Chestnuts make sizeable trees relatively quickly).
This tree has sap-runs oozing out of folds in the trunk and also in one of its larger branches. It also
has a sizeable wet rot-hole at its base full of decaying wood and with an internal sap-run. It also has
rot-holes in the main trunk, dead wood, accumulations of wet leaves caught in buttressing at the
trunk base and also has a Ganoderma bracket fungus at its base. The following saproxylic flies
have been recorded on this hee:
Aulacigaster leucopeza Ferdinandea cuprea
Brachyopa insensilis Mycetobia pallipes
Brachypalpoides lentus Xylota xanthocnema
Criorhina ranunculi Systenus pallipes
Brachyopa insensilis and Aulacigaster leucopeza have been found on numerous Horse Chestnut
sap-runs in the park, particularly in the formal gardens. Even quite small trees can provide useful
habitat. I have found a well-developed rot-hole in a tree with a girth of just 20 inches (51 cms),
another Horse Chestnut with its trunk shattered by the 1987 storms at 2ft (61cms) above ground
level and with re-growth around the rim shading a well-rotted and leaf-filled interior has provided
two reared records of the nationally notable beetle Prionocyphon serricornis and the fly Systenus
scholtzii. The two Red Data Book flies Callicera spinolae and Callicera aurata have also both
been reared from rot-holes in Horse Chestnut at Wimpole Hall in Cambridgeshire (but other species
are recorded as well) and it is likely that these two species are using some of the many suitable
Horse Chestnuts in and around the formal gardens area. Criorhina ranunculi, found new to Essex
at Hylands, is another species I noted around decaying parts on the lower trunk of Horse Chestnuts.
Beech Fagus sylvatica is a significant and important tree for saproxylic species at places such as
Epping Forest, Windsor Forest and Burnham Beeches, where it is probably native and found in
numbers. This is not the case at Hylands, where it is found only in very small quantity and all are
planted. Of the dozen or so large trees (mainly in the Writtle Belt) at least 9 are dead (including one
of the Copper Beech trees in the formal gardens). The dead trees would probably be worth
investigating for their beetles and at least one dead tree has the ant Lasius brunneus nesting in it.
Beech does not seem to thrive at Hylands, but new trees have been planted in some of the plantations,
presumably in the 1970s.
Essex Naturalist (New Series) 20 (2003)
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