Teresa Hughes is our guest blogger today. An Ecologist and Environmental Advisor with Historic Environment Scotland (HES), she brings us up to date with successful nature-friendly steps being taken around one of Scotland’s most famous historic and spiritual sites, Iona Abbey.
All the staff at Iona Abbey have recently embarked on a bit of a ‘grassland revolution’. Visually, as well as ecologically, this has had a beneficial impact. We’ve adopted three different types of mowing across our site and are noting considerable ecosystem benefits from the changing habitat structure.
“What are the new approaches?”, I hear you ask.
We have long-grass areas that will only receive one annual cut. That cut doesn’t take place until mid-August at the earliest as this will allow for a lengthy flowering period and for seeds to set. We also cut this from the centre outwards to allow small mammals and sheltering birds and insects ample escape routes. These areas provide a valuable source of food for pollinators and ground cover for small mammals.
Our medium areas are maintained at a 150 to 200mm sward height. Cut more frequently than our long grass areas the medium area nevertheless has low growing flower species such as clovers and bird’s-foot trefoil. These provide a fantastic resource for pollinators, and the cuttings will be removed to keep nutrient levels in check helping the flowering plants to flourish. This level of sward and more regular cutting will simultaneously ensure the underlying archaeology and interesting ground features remain easy for visitors to appreciate and see.
Finally, our short cut grass areas. Here the aim is to ensure that the Abbey itself is framed, and simultaneously visitors can see that the surrounding grounds are actively managed.
One of the most obvious outcomes of our change in mowing approaches is a pleasing increase in the diversity of flowering plants. That’s good news for pollinators, of course, but it’s clear that the longer grassland is providing substantive benefits for other species. I am confident that year-on-year we will see increases in floristic diversity too.
Longer grasses provide cover for moths, butterflies and a range of other insects. The longer length of grass protects against rain to some extent, provides shelter against wind, and is a slightly warmer place. This is particularly important when the weather is changeable and showery.
That showery weather can create interesting insect encounters. Visitors, of which there are thousands, might notice that after rain, when walking through the longer grass, more insects are ‘put up’ as they have been sheltering near the bottom of the grass.
Several species of butterfly, like the meadow brown, use grasses to lay their eggs on, and likewise many other caterpillars’ and moth’s food plants are grasses.
The orange tip butterfly is also found on Iona, and feeds on the early flowering lady’s smock. In addition the species has been using the longer grass cover for its overwintering stages.
The white clover that was already present, provides plentiful nectar for bumblebees. Those species with tongues long enough to reach into the nectary at the bottom of each of the many little flowers that make up the head of the clover flower are set to benefit.
It isn’t only insects that are reaping rewards from the new approach. Grasses and other plants, like common sorrel, have seeds which some birds eagerly feed on. Brightly coloured goldfinches have been taking advantage of the burgeoning seed source. In July there were several family groups in evidence around the Abbey and come winter the longer grass will provide cover and feeding for ‘charms’ (the lovely collective noun for a group of goldfinches) as they gather in winter flocks. They can balance and feed on the slimmest of perches, and are a delight to see feeding and flying around the Abbey.
Staying on the theme of birds, corncrake was recorded calling from within the Abbey grounds this summer by colleagues working for the National Trust for Scotland. The long grasses behind the Abbey grounds were providing cover for this shy bird, which breeds in the fields close by.
Another interesting record this year saw common lizard logged, these were sighted on the rocks and taking advantage of the plentiful long grass cover.
The grassland changes and pleasing visual impact is bringing about a nice cultural change from both visitors and colleagues. As many a local authority will testify, it’s not an easy ride changing grassland management practices. The ‘practicalities’ of meadow management can throw up challenges in terms of equipment, knowledge, and perception. However, at HES, we are hoping that the thoughtful and incremental changes seen at Iona Abbey will, in time, make a positive impact on our estate as a whole.
Find out more about Historic Environment Scotland’s grassland revolution and similar works carried out at Dryburgh Abbey.
Scottish pollinators 