Butterfly Bank at Moira Furnace

Update Number 5.

Moira Furnace lies in the heart of the new National Forest, in the west of the county, bordering Derbyshire. Monitoring flora and fauna is one of the keystones to the development of the National Forest and will directly influence future action plans as and when the need arises. As far as Lepidoptera are concerned, we already have butterfly transects set up at Hicks Lodge, Sarah’s Wood, Pick Triangle, Donisthorpe Woodland Park and Willesley Wood, so we should be able to build up an accurate picture of the status of our butterflies and moths in the Leicestershire section of the Forest. So why, then, do we need a Butterfly Bank?

Butterfly Banks can be regarded as an ‘all-in-one’ butterfly habitat, providing places to bask in the sunshine, and to provide both nectar and larval food plants. Stepping stones in the natural landscape. Moira Furnace adjoins the site of one of our existing transects, namely the one at Donisthorpe. One of the key species we hope to attract to the Butterfly Bank is the Dingy Skipper, and this has been recorded on the transect at Donisthorpe, a mere half a kilometre away. It is no great leap of faith to expect the Dingy Skipper to appear at Moira Furnace.

The Project was a joint venture between East Midlands Butterfly Conservation, the National Forest (Black to Green Project), OPAL (Open Air Laboratories) of Nottingham and the Ashby and Coalville Lions. Work began in March when the construction process took place.

Removal of the existing Topsoil

I would say the simplest way to describe the process of constructing the Butterfly Bank is to think of gardening ‘in reverse’. Normally you would expect to have the nutrient rich soil on the top and poorer subsoil below. To give the wildflower plants the conditions they need to grow in, these have to be reversed. Too much nutrient would give lush, rich growth that would succumb to pest and disease attack, and also result in fewer flowers. Low nutrient levels mean tighter, more compact plants and greater flower production and seed set. Once the topsoil had been removed and stacked, a trench in the shape of a large ‘C’ or ‘armchair’ was taken out and the subsoil set to one side.

Topsoil being placed in the bottom of the trench

The topsoil that had been removed was then placed in the bottom of the trench and covered with the subsoil forming a ridge approximately 75 cms (30 inches) high. The ridge was higher in the centre (forming the back of the ‘armchair’) and tapering to about 40 cms (16 inches) on the ‘arms’. Once the soil had been shaped the whole Bank was covered with TWO layers of stone. The first layer was of crushed limestone (similar to Type 1 roadstone). Calcareous stone is most suitable for Butterfly Bank construction, but in this case there was far too much fine material (almost dust) and the fear was that under heavy rains this would compact and become impenetrable to plant roots. It was also a concern that the action of winter rains and frosts would cause further fragmentation. The decision was taken to add a layer of harder ‘drainage’ stone (granite) to cover this layer, giving protection from the harsher elements whilst still allowing moisture through to the plant roots below, and to provide a rough surface for plants like Bird’s Foot Trefoil and Creeping Cinquefoil to scramble through. This layer was also more aesthetically pleasing, taking into consideration that the site will be subject to considerable passing foot-flow.

Calcareous sub-layer  


Granite Top layer     

Once the bank was covered it was left for a couple of weeks to allow for settlement prior to planting.

The completed Bank prior to planting.

The wildflower plug plants duly arrived and with the help of the Lions and the local Scout group, planting took place on an overcast but dry morning (perfect conditions, I’d say….). The areas adjoining the bank and directly opposite were also to be planted to create wildflower meadows to compliment the Bank. Plant species were selected to attract some key species of butterfly. Bird’s Foot Trefoil was planted specifically for the Dingy Skipper; Sheeps Sorrell for the Small Copper and Common Rock Rose for the Brown Argus. Perhaps more ambitiously, or even optimistically, Creeping Cinquefoil was planted to attract the elusive Grizzled Skipper. The latter species may never appear here, but ‘you never know’. The meadows were planted with a host of nectar and larval food plants for butterflies and moths, and also by default, bumblebees.

Healthy wildflower plug plants sourced locally from Naturescape in Notts.


Local Scouts planting on and around the Bank.


….and in the Wildflower meadow…

The measure of success of the Butterfly Bank will only become clear as we monitor the butterflies and moths that move in over the coming months and years. To ascertain this, a program has been set up to record the Bank throughout the season. Visits will be made on a fortnightly basis to record species using the bank and neighbouring meadows. Should the Bank prove successful, plans are afoot to create another in neighbouring Donisthorpe Woodland Park, and subsequently in other key sites in the National Forest, creating ‘stepping-stones’ for our region’s butterflies and moths and aiding their survival and potential expansion of territory.

I will keep you updated on the progress of the Bank and on the species recorded on and around it……..and should a Dingy Skipper appear, you’ll be the first to know.


Posted in Leicestershire and Rutland Butterfly Line, News.