Conservation Evidence strives to be as useful to conservationists as possible. Please take our survey to help the team improve our resource.

Providing evidence to improve practice

Individual study: Influence of alternative foods on vole population and damage in apple orchards

Published source details

Sullivan T.P. & Sullivan D.S. (1988) Influence of alternative foods on vole population and damage in apple orchards. Wildlife Society Bulletin, 16, 170-175


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Provide diversionary feeding to reduce crop damage by mammals to reduce human-wildlife conflict Terrestrial Mammal Conservation

A randomized, controlled study in 1983–1984 at an orchard in British Columbia, Canada (Sullivan & Sullivan 1988) found that diversionary feeding with treated plywood sticks did not reduce damage by voles Microtus spp. to spartan apple Malus domestica trees. The percentage of apple trees damaged by voles did not differ significantly in orchard blocks with treated plywood sticks (32%) or those without sticks (36%). Trees with treated plywood sticks around them had more bark and tissues removed by voles (average 20–27 cm2/tree) than trees without sticks (5 cm2/tree), although the difference was not tested for statistical significance. In November 1983, three treatments (plywood sticks treated with sucrose, soybean oil or sorbitol) were randomly assigned to each of three orchard blocks of 100 spartan apple trees (15 and 30 years old). Three plywood sticks (5 x 37.5 cm, 9 mm thick kiln-dried Douglas fir Pseudotsuga menziesii) were placed in a triangle around each tree, 1–2 cm from the base. One control orchard block had no plywood sticks. The area of bark and vascular tissues removed by voles was measured on each of the 400 trees in March 1984.

(Summarised by Anna Berthinussen)

Provide diversionary feeding to reduce crop damage by mammals to reduce human-wildlife conflict Terrestrial Mammal Conservation

A randomized, controlled study in 1984–1985 at a newly planted orchard in British Columbia, Canada (Sullivan & Sullivan 1988) found that diversionary feeding with bark-mulch logs treated with soybean oil reduced damage by montane voles Microtus montanus to crabapple Malus spp. trees, but logs treated with apple or apple and soybean oil did not. Orchard blocks with logs treated with soybean oil had a lower percentage of trees damaged by voles (25%) and trees with stem or root girdling (4%) than those without logs (63% damaged; 25% girdling). The difference was not significant between orchards with logs treated with apple (46% damaged; 17% with girdling) or apple and soybean oil (58% damaged; 33% with girdling) and those without logs. In November 1984, logs made from sifted Douglas fir Pseudotsuga menziesii bark mulch mixed with wax and one of three treatments (soybean oil, apple powder or apple powder and soybean oil mixed together) were randomly assigned to each of three orchard blocks of 24 one year old crabapple trees. Three logs were placed around each tree, 8–10 cm from the base. Additional logs were added as required in December 1984–February 1985. One control orchard block had no logs. Numbers of trees with vole damage and stem or root girdling in each of the four orchard blocks were recorded in March 1985.

(Summarised by Anna Berthinussen)