Dr. Deer’s Prescription

Fencing for Whitetails By Dr. James C. Kroll

Ibet when you saw this title, you thought I would discuss some aspect of high fences! High fences are used mostly to keep deer in, but I’m talking about fences to keep deer out. The four-plus decades of work here at the Institute for White-tailed Deer Management & Research has led to a host of technological advances in deer management, including food plots, feeds, minerals, trail cameras and many more. More often than not, our discoveries were way ahead of their time and not well accepted when we first released them.

For example, would it surprise you the first two startup companies we worked with in developing trail cameras went bankrupt, because hunters saw no application for them? Back in the late 1970s and early 1980s, we conducted the first research on food plot varieties and preferences by deer for specific plant varieties. Among these were cowpeas, which have been grown for hundreds of years for human consumption. There was a time when you could plant a patch of black-eyed peas and have few concerns about them growing to produce peas for the table. However, as deer populations grew, pea gardens came under attack.

I never will forget the first time we tested peas in our food plot research plots. The deer never touched them, and I decided at least we would get a good crop of peas for the freezer. I remember checking the plots one day, confirming it was time to pick the next day. Arriving at the research plots, every pod had been carefully removed from our plants.

My first assumption was someone had sneaked in and picked our peas. After examination, however, we found deer tracks all

The author inspecting electric fencing. Such fencing makes for a good method of keeping deer out of food plots until the plants have had a chance to grow.

through the plot. The next night, they returned to start eating the vines. It turned out the deer had no experience with these plants, but as the summer progressed, they apparently had decided to test them. Shortly after, farmers began calling about deer damage to their crops, which led us to a new direction in food plot research.

The problem, often with warm-season food plots such as peas, corn and soybeans, is they can be classified as “ice cream” plants. That is, the plants are so highly preferred that deer eat them, even when perfectly good native plants are available. What good does it do to plant them to supplement your deer nutrition, when they truly need supplementation, only to have them destroy the plots before then? We began looking for a workable and affordable solution.

At the same time, we became interested in deer vision. Namely, what colors can they see and how well do they see? Research by southern biologists pointed to the fact that, for one thing, deer are nearsighted and have poor depth perception. These discoveries would figure significantly in our research program. A chance discussion with some folks from the Soil Conservation Service would supply the answer—electric fencing. Our colleagues worked on using new technologies out of New Zealand for ways to implement high-intensity, shortduration grazing for cattle and sheep. Bill Gallagher was a New Zealand farmer, who in the 1920s, devised the first electric fence for livestock. It all started with a horse named “Joe,” that took a liking to scratching on Bill’s vehicle. Irritated to the point of distraction, Bill devised an ingenious electrical system that would generate electricity as the vehicle rocked back and forth, shocking the perpetrator. By the 1930s, Bill had perfected and marketed the first electric fencing systems, which even today, are the best in the world. We decided to develop a system that would work for deer.

We tried all sorts of configurations, starting with essentially a high fence made up of 22 runs of high tensile wire. It worked fine, but the amount of work to install the fence, plus the cost, was prohibitive for the average landowner. We then went to offset fencing designs, starting with a slant fence only 4 feet tall. Again, it just took too much work to install this design.

Then we considered what had been learned about deer vision. Since they have poor depth perception, it seemed obvious to us that a three-dimensional fence would work. We decided on only three wires, one as an outrigger at 18 inches above the ground and two more inside at 12 and 24 inches. The distance between the two was set at 36 inches.

To our amazement, deer would not jump the fence, provided it was energized from the moment it was installed. In those days, we used high tensile wire, strung to 1,100 pounds of tension, requiring sturdy corner braces. Again, this was a bit much to expect of landowners, yet several adopted the design. The fence was energized with one of Gallagher’s high-voltage, battery-powered units, generating a whopping 7,000+ volts. The amperage is relatively low and the “duty cycle” for the charge was extremely short—one second—making it safe to use on almost any species, including humans.

Later, Gallagher and other companies would perfect synthetic wires, reducing significantly the need for strainers and heavy braces. Today, one person can construct a fence around a oneacre food plot in less than half a day, making the fence not only effective, but also economical. The fences are in common use today; and, as would be expected, many take credit for inventing them. But this does not matter because the fences work!

Now, let’s talk about how we use them.

Late summer is a significant nutritional stress period for whitetails. Does try to keep up with a high nursing demand by growing fawns, and bucks pour much of the nutrition they receive from food into their antlers. Where climate permits, summer food plots are critical in achieving the maximum potential from your deer herd. Our food plot research led to a firm recommendation for cowpeas in the south and a mixture of soybeans and corn in the north.

We fence the plots just after planting and keep them running until the deer need them. We check on the fences regularly to assure they still function. Allowing a fence to go down leads to deer finding out they can jump into the plot. We use a solar recharged energizer and marine battery combination to power our systems. We still use some of the Gallagher energizers purchased in the late 1970s, so the cost of the fences is neglectable at this time.

We have applied this technology to what amounts to “rotation grazing” systems for whitetails. We have several plots located around a property and open the fences to the deer periodically until they eat half the crop. Then, we close the fence and open another. You can see why we call it rotation grazing.

However, there is one very important detail. You must place two gates in the fence, one at each end. If you do not, your sudden appearance or that of a coyote on the end with a single gate will put the deer right through the fence. By installing two gates, this gives your deer an exit point, opposite of where you appear. We have even applied this technology to create “strip grazing” systems on powerlines and other rights-of-way, where we use spools to retract the wire to allow deer to feed on the newly exposed area.

Lastly, some of our cooperators are small landowners, who shall we say, have problematic neighbors who shoot every buck that jumps the fence. In such cases, we plant a mix of corn and peas (soybeans), fence them until right before deer season, and then take down the fence. The result is that you essentially “own” the deer. We often mow strips through the planting in the shape of the old “turkey track” design used by so many south Texas hunters, with the base of the track culminating at the deer blind.

In my next column, I will discuss subsequent research on polypropylene netting to do some of the same things.

This video capture shows a yearling buck learning the hard way about electric fencing.