Last weekend Bog Squad volunteers tackled an invasion of pine at Peeswit Moss SSSI near Penicuik in Midlothian. This lovely bog is one of the few remaining lowland bogs in the Lothians that the Large Heath butterfly can still be found. Unfortunately old drainage ditches cutting across the moss surface have left it drier than it naturally would be.
This has led to increased heather growth and invasive pine scrub is seeding onto the moss from nearby woodland. These changes create further problems on bogs as thick heather cover and scrub intercepts rainfall, causing further drying. It can also be bad news for the Large Heath butterfly, which relies on shorter mossy vegetation coupled with lots of cottongrass. Scrub and heather can easily shade out the habitat niche that the Large Heath requires.
The Bog Squad's task at Peeswit was to remove all the pine scrub from the moss by pulling, heaving, sawing and lopping. The volunteers set about the task with great gusto and it wasn't long before the thickest area of pine was looking very sparse indeed. And by the end of the day all was gone!
The work carried out by the Bog Squad complements larger-scale work at the site carried out earlier this year funded by Peatland Action. The old drainage ditches were blocked up with peat dams that will help to slow water loss from the moss. There was good evidence already that the work had been effective with pools of water froming behind the dams and sphagnum mosses growing well. By making the moss a wetter place, invasive pine scrub is less likely to take hold in the future. And hopefully this means that Peeswit Moss has a soggy carbon-rich future ahead!