© Laurie Campbell 2005
Twinflower (Linnaea borealis L.) is a creeping perennial which spreads vegetatively, producing patches of clones which are self-incompatible (i.e. plants cannot fertilise one another when pollen is from another plant of the same clone). Now restricted to the pinewoods of NE Scotland, twinflower was once more widespread, occurring in old pine plantings in northern England. Heavy shading is considered to be one of the main threats to the species, as it is thought to kill the plants but some light shade is necessary for good growth and flowering.
A key target in the Species Action Plan is to achieve self-sustaining populations capable of sexual regeneration.
Understanding what light levels are most beneficial and how these can be achieved through stand manipulation is important.
A collaborative project between Plantlife, Scottish Natural Heritage (SNH) and the Forestry Commision is underway at a privately owned mature pinewood in Speyside which has been thinned to an experimental design. Forest Research, SNH and consultant Ruth Maier, have been monitoring responses of 26 twinflower colonies before, immediately after, and one year after thinning; plot light levels and stand characteristics have been assessed pre- and post-thinning.
Preliminary results suggest increased light levels and/or disturbance have a detrimental effect on twinflower growth and flowering but it will be several years before the colonies are expected to respond fully to the treatments.
