Using ‘Micro-Exclosures’ to Deter Deer

Deer can be an occasional irritation or a constant threat to the garden, and the Internet is full of remedies. But much of this flood of advice is so questionable that it borders on folklore. Commercial repellents work, but they can be costly over time. How can you deter deer?

Recently, I’ve experimented with what I call a “deer micro-exclosure,” and in cooperation with the Regional Sustainable Development Partnership of the University of Minnesota Extension, we’ve found its effectiveness approaches 100 percent when it is built according to specifications.

Micro-exclosures can be any size or shape and built of a variety of materials, but they must be at least 4 feet high to deter deer. The ones I built were made from 16-foot cattle panels. The four panels were secured using cable clamps at three of the corners, with one left open to allow entry to the area. A steel T-post was secured at the center of each side to stabilize it. While 16-by-16 is not large, the enclosed area could produce hundreds of dollars worth of vegetables or protect a special nursery plot or safeguard parent stock of a prized hosta collection.

Here’s why it works: Deer are afraid of being trapped and micro-exclosures create a psychological roadblock. The operational assumption is that deer make judgments relative to safety. If an area appears too small, they will not risk entry even when the fence is fairly low because they don’t want to be trapped there. If a breach occurs, it is easily resolved by making the enclosed area appear smaller. Simply string a visible wire, hung with flagging, across the center to reinforce the sense of enclosure. While we know deer can adapt to new situations, the preliminary results of this method are excellent.

Guess what else works to deter deer? Homemade egg spray! The same project found that homemade egg sprays worked as well as commercial sprays most of the time. A simple formula of three eggs thoroughly blended into a gallon of water that is used regularly and reapplied as needed was reasonably effective at deterring deer.

This article by Kent Scheer originally appeared in the March/April 2019 issue of Northern Gardener. Kent owns Green Island Preserve, a nature area open to the public, in Wadena, MN. He welcomes your observations and feedback on these or other deer control methods at kentscheer@outlook.com.