Stanmore Common Nature Trail
Long trail post 2:
This is Holly Brook, one of the many streams on the Common. The streams used to flow all year around but now flows are sporadic due to drier summers.
In summer look for water crickets upstream of the bridge. These are not crickets but are members of the Hemiptera, the True Bugs. They skate on the water surface like Pond Skaters but unlike the latter have bent front legs (see image). Both pond skaters and water crickets are predators on drowning insects, detecting them by sensory hairs on their legs.
Image: Water cricket copyright David Fenwick Snr
A close look at the stones in the stream will show tiny snails who graze microscopic plants from the hard surface. These are Hydrobia snails with 5 UK species.
The water is unpolluted by the time it reaches the lower valley and pollution sensitive insects such as stoneflies appear.
Finally look to your left along the bank of the Holly Brook. Small mouse like mammals called Bank Voles have been seen here.
Just beyond the footbridge on your right is a colony of Broad Buckler Fern growing on the root plate of a fallen tree. This fern is identified by the brown scales down the stem. The scales have dark centers.
As you continue uphill you can see lots of fallen and dead trees. It is policy on this reserve to leave dead trees intact as part of the natural decomposition and regeneration of the woodland. The trees leave important holes in the tree canopy, allowing light in.
As you continue just beside the path are many Rowan trees with their smooth grey bark with the characteristic horizontal breathing pores or lenticels. These trees are spread by birds pooing out the seeds from the berries.
Many trees here are covered in ivy a climbing evergreen plant. Ivy does not kill trees and it is a very valuable resource, flowering very late in the year. Ivy honey is beautiful. Ivy is the foodplant of the Holly Blue Butterfly and bats prefer ivy covered trees to nest and roost in.
description for long trail post 3
More on some of the birds you are likely to see or hear on the Common
More on the three species of deer on the Common and their tracks
here to learn more about the Harrow Nature Conservation Forum including
guided walks and conservation workdays.