Efficacy Testing Using Commercial Animal Repellant

Damage inflicted by animals to plants growing in the garden and in the landscape is a problem that persists, and in some areas is increasing. Deer, squirrels, woodchucks, and rabbits are among the most damaging and annoying of these pests. Exclusion of animals with mesh fences, electric fences, and other devices to prevent animals from getting at plants is often the most satisfactory solution. However, fences may be expensive, unappealing or impractical, especially if one chooses to protect plants in the landscape.

Some homeowners do not grow gardens anymore due to a history of animal damage. There are a number of natural animal repellants on the market that are intended to be sprayed on plants to stop or reduce feeding damage caused by wildlife.

In research experiments, corn was sprayed with these repellant ingredients where there was a dense population of deer, rabbits and squirrels. The portion of corn consumed by the deer, rabbits and squirrels in one day was determined and this was the basis for evaluating the relative effects of the repellants in the test.

Repellant ingredients differed widely in their ability to deter animal feeding (Table 2). The control received no treatment and should be considered the amount of feeding that would occur under natural conditions. The damage to plants, shrubs and trees in landscape is a function of animal pressure. When animals are very hungry they will eat plants, even if they do not taste good. However, when they have a choice, they will eat the more desirable vegetation.


Table 1.

Table 2.

Efficacy Testing Using Nature’s Defense Granular Animal Repellent

There is considerable evidence to suggest that wild animals avoid feeding on some species of cultivated plants, active ingredients found in the Nature’s Defense organic formula.  These plants produce substances that wildlife find offensive to eat.

In additional research experiments, corn feed stations were set up to test the Nature’s Defense granular animal repellant. There was a dense population of deer, rabbit, squirrel, raccoon, groundhog, chipmunk and mice feeding regularly at the test stations. Corn was placed in two test areas by electronic feeders set on timers releasing corn three times per day. Test site one was treated with Nature’s Defense granular animal repellent at the recommended rate. Test site number two, the control site received no treatment and should be considered the amount of feeding that would occur under natural conditions.

The portion of corn consumed by the deer, rabbit, squirrel, raccoon, groundhog, chipmunk and mice in one day was determined and this was the basis for evaluating the relative effects of the repellant in the test (Table 4).

Table 3.

Table 4.