June 12th, 2007

Most of today was spent walking around Mynydd Illtyd - the common land surrounding the mountain centre in Libanus. We visited a small pond feature which was being invaded by pond weed. Paul - the chief ecologist for the park - said the best treatment was to wait until the pond had dried out in the summer then dig it out. The weed is a highly invasive non-native species originating from garden ponds and can soon block out any sunlight for other species.

The area supports semi-natural acid grassland and the main issue in this area is the encroachment of bracken and gorse. There are various methods used to control the bracken but because it is common land and there are grasziers rights it can be difficult to manage. Ideally the area would be grazed by welsh mountain ponies or a hardy (and people friendly) breed of cattle as they are better at grazing the gorse and poaching the ground. The levels of grazing have fallen in recent years - particularly after the foot and mouth epidemic - and this has exacerbated the braken and gorse problem.

Gorse can be chemically treated with a weed killer that specifically targets woody growth, or it can be cut. Bracken should never be burnt as the seeds thrive after being heated. Bracken can be rolled, cut or treated with chemicals. The general regime is to roll for three consequtive years and the aim is to starve the woody rhizomes. If the ground is to bumpy or the bracken is to short and bushy (which tends to happen in the 2nd year of growth) then cutting can be more effective. Another issue that was discussed was that any control regime is expensive and as soon as the money dries up and control stops the bracken and gorse will soon re-establish.

Later on in the day we saw some small pearl bordered fritillary caterpillars on some bracken and also a common newt - which can be distingished from other newts by the stringy bit on the end of it’s tail and it’s spots. Males can be distingushed from females by the huge set of testicles at the base of their tail!