Boblainy Forest is a large commercial plantation forest owned (mainly) by the Forestry Commission on the outskirts of the village of Kiltarlity. This is my local stomping ground and on Saturday I was involved in leading a walk though the forest.
I love the morning mists we often get at this time of year as we drift from high summer into autumn. Yesterday was one such day and it was wonderful to see an abundance of spiders webs on our walk in Boblainy Forest. As the dew droplets settle on the threads and allow them to be seen we see just how numerous they are.
Spider webs fall into several types. The simplest are the numerous tangle webs or cob webs. These look like a haphazard array of threads; they are frequently seen among our window sills (inside and out in my case!)
Sheet webs that resemble silken hammocks were numerous along the woodland edge on the grass and shrubs. Some ‘Christmas trees’ (spruce) were decorated just as if with snowy tinsel.
The large circular (spiral) orb webs were found decorating the gorse and broom shrubs at the path edges. They are the best known web form and are thought of as the ‘typical’ spider web.
These webs can be very large and consist of a number of basic support wires. The basic wires are not sticky and used by the spider as foundation for the web. Attached to this foundation are numerous sticky wires called radii. Finally, many spirals of silk are laid down over the radii. When the spider is not in the centre of the web, it is at the edge, hiding under a leaf or something with two legs touching the web. If prey is caught some place in the web, the spider knows where in the web the prey is caught by the vibrations transmitted to her via the radii.
While orb webs are often knocked down and rebuilt each day, sheet webs will last for many days or weeks before being abandoned.
The main track through the forest is like that in many commercial pine or spruce forests and rather uninteresting, but here at Boblainy in many places it is at least edged in a variety of shrubs and deciduous trees.
The main through-route was improved several years ago to open up the farther corners of the forest for harvesting of the trees.
However felling of trees and removal of the cut timber was halted last year due to a moth pest and stacks of timber are piled along the forest road.
The pest causing the trouble is the pine-tree lappet (Dendrolimus pini) a native of continental Europe, Russia and Asia, where the caterpillars feed primarily on Scots pine needles. The Forestry Commission is concerned that it could become a pest in this country.
Forestry investigators and moth experts investigating the status of the population after small numbers of male moths were found have now discovered a number of larvae (caterpillars) and a cocoon, indicating that the species is breeding.
Pine-tree lappets had not previously been recorded in Scotland, so the species might be a previously undiscovered resident, or a recent arrival. It had previously only been recorded in Great Britain from a handful of sightings over several decades of individual males in southern England. These are believed to have been migrants from Europe.
Using pheromone and light traps, sticky bands around trees and searching in the ground litter, Forestry Commission investigators and amateur moth recorders have discovered about 100 adults, some caterpillars and a cocoon since the summer in woodlands west of Inverness. These include Forestry Commission Scotland’s Boblainy Forest.
The investigations were prompted by the discovery of a small number of male moths in the area last year, following discoveries of one in 2004 and two in 2007, which were not reported to the Commission at the time.
One positive point aspect of this pest is the felling and extraction has ceased, so the forest is quiet again with no chain saws and no timber lorries.
There are numerous open areas in the forest, including areas of recent felling and places now cloaked in heather indicating more long-term removal of trees.
One of the hazards of a working forest is the track and paths on the ground do not match what is marked on the map. The recently-formed community forest group are trying to produce a more up-to-date map and have been exploring many of the side tracks. We also spent several days earlier in the year cleaning the paths of the numerous trees and branches brought down in last winter’s snow. As we saw on Saturday, some of these minor tracks appear to have been used by 4-wheel drive vehicles and are very muddy. Goodness knows what the people are doing driving into the woods. Poaching? Fly tipping? Taking timber? There are gates at the entrances to the forest, but for the past couple of years the FC have not kept these locked.
We completed an ‘End-to-End’ 6 mile walk on Saturday – with car-sharing between the start and finishing point. We plan to run more circular walks in the forest once we have fully investigated and cleared more of the minor, currently overgrown, paths.