Twelve-year-old working horse Tyler spent a day "bracken bashing" on a meadow near Oswestry to give the violets that grow underneath the bracken the chance to flourish.
Common dog violet leaves are the favourite food of the caterpillars of pretty, pearl-bordered fritillaries – which are found on only three sites across Shropshire. Shropshire Wildlife Trust is hoping providing a plentiful supply of dog violets on meadows at Nant Mawr could help increase the numbers of butterflies.
Barbara Haddrill, from Carnog Working Horses, based in Llanrhaeadr-ym-Mochnant, travelled to the fields with her heavy horse Tyler on Thursday.
The fields lie next to Jones' Rough in the Oswestry hills, one of seven nature reserves owned by the Wildlife Trust in the area.
Dense bracken is engulfing the habitat of the pearl-bordered fritillary, in the area.
Barbara and Tyler spent several hours dragging a "bracken basher", a traditional horse drawn implement, across the six foot high vegetation on the meadows.
Sarah Gibson from Shropshire Wildlife Trust, said: "This is an excellent area for wildflowers and control of the bracken will allow these plants to spread.
"Violets grow well under light bracken until it grows too dense, when the violets are shaded out."
Barbara said: "Working horses were a common sight in this area in the not-too-distant past, especially working on the steep wooded slopes and fields where man-made machines still struggle to reach."