Oh deer!  Deer damage and what farmers can do about it

Oh, deer! At least it is a wintertime visit.

Oh deer! Deer damage and what farmers can do about it

Published May 21, 2018 

It is that time of year again, at least in my parts. As things go from the tunnel to the field, all our friendly little four legged foes start to to make dinner plans… and breakfast plans. Some are making midnight snack plans as well. Raccoons, rabbits, and the worst of all in our area - deer.

Animal damage to ag crops is a significant issue. How significant? How is a over billion dollars per year? 

“The National Agricultural Statistics Service (NASS) estimated that losses to field crops, vegetables, fruits, and nuts exceeded $765 million USD in 2001. White-tailed deer were responsible for 58% of field crop losses and 33% of losses to vegetables, fruits, and nuts. “

Even worse, the amount of damage deer are doing to crops is increasing. A number of factors are driving this trend, none of which bode well for deer driven crop damage in the coming decade.

For certain vegetable crops - sweet potatoes, certain greens and the like - deer damage can be catastrophic. A pack of deer can graze down a tenth of an acre of sweet potatoes in just a night or two (Don’t ask me how I know…). An entire acre or crops won’t make it a week if you have heavy deer pressure.

While deer populations are increasing, amount of people hunting deer is declining.

The decline in hunting should worry farmers especially. In my home state, the increasing deer population and lower hunter participation is leading to increased season lengths and other measures to bring balance, but many of us realize that this won’t fix the problem or address the root issue. An extra week or so of hunting doesn’t increase the bag limit or total number of deer taken substantially, and it doesn’t do anything to help us during the growing season.

Oh deer!  Deer damage and what farmers can do about it

So, we are looking at measures to minimize damage and make investments that will protect our crops and want to hear what others are doing as well.

Approaches to minimizing deer damage

So, what can a farmer do to protect their crops from nonpaying customers?

Encouraging Hunting

If possible, encourage responsible hunting on your land. Yes, there are less hunters. This means if you want them to help control the population in your area and protect your farm, you need to make your place an attractive option to the ones that remain. In my area, I know many people who not only want to hunt, but will do so with the utmost care for my land. They are busy folks, so they are looking for an enjoyable place to hunt with a high likelihood of success. Thus, their needs and our problem becomes a match made in hunting heaven.

Our goal this fall is to between our family’s bag limit and then allowing a few others to take at least eight to ten deer. Allowing hunting on your own land alone may be insufficient to control exploding deer populations - farmers also need to get other community members and land owners involved.

How about fencing?

Fencing out deer is possible, but not always financially or otherwise feasible. A fence tall enough to exclude deer (eight feet high), may turn into a massive expense. For multi-acre operations, such an approach is often cost prohibitive. Some companies have developer lower cost ways to improve the deer deterrence value of shorter fences.

These fence additions are far less expensive than a chain link, woven, or similar fence of sufficient height needed to exclude deer. Also, some of these fence extenders that use an angled, outward sloping approach are more effective than simple, vertical fencing and fence extenders. The outward sloping angle of the fence extenders is a better deterrent to deer than a purely vertical fence. Some farms now build their animal fencing sloping outwards for this reason, trying to get double duty from a single investment and expense.

“Height, or width, is probably the most important factor with deer fences, especially if high deer pressure. White-tailed deer can jump almost eight feet high, so effective upright fences against them should be this high. Deer may be able to jump high, but not both high and over a distance. So a fence may not be as high, perhaps six feet, but slanted outward. The deer will try walking under the fence and meet resistance. Such a slanted fence should be at a 45-degree angle, and may consist of fencing with a few strands of additional wire on top for extra height.”

You can read more about fencing out deer effectively here,

Livestock Guardian Dogs

A number of farms have started to employ their livestock guardian dogs (LGDs) to also keep deer away from sensitive areas and edible crops. A number of farmers I know are using this approach exclusively instead of fencing. The benefits are many, since LGDs provide protection to their livestock along with crops, trees, and other investments in their mixed agricultural operations.

Also, the use of dogs isn’t completely uncharted territory. The effectiveness of LGDs, especially teams, has received some study with positive results reported.

“Deer damage to apple trees in commercial orchards is a major problem for growers in Maryland and surrounding states. The use of dogs contained within "Off-Limits Crop Protection Systems" has been shown to be an effective way to reduce deer damage in orchards in New York State.”

Unfortunately, dogs have clear acreage limits. For smaller operations, especially vegetable growers, orchards, tree stock (or tree establishment), nurseries, or operations with similar crops and the like that are 15 acres or under, dogs are probably the lowest cost solution to mitigating deer damage. Beyond that, things become more complicated as teams of dogs will need to be spread out across the property to provide better coverage and deterrence.

Note, while dogs will lessen deer damage, they won't completely stop it.  But neither will any of the other measures, apart from turning your farm into Fort Knox.  Also note, dogs destined for deer patrol may need additional encouragement and training.   If you think keeping a dog leashed or in some kind of run will help, studies show it won't. Deer are too smart for that.

Thankfully, if you also have livestock, dogs may pull double duty, protecting your crops from a wide variety of pests while also helping reduce predation on your livestock.

Electronic Devices - Sights and Sounds

Some companies are now offering various electronic deer deterrents. Some of these are quite simple - motion activated lights, which with advances in solar power are easy to deploy in almost any place and easy to move around. Some use motion sensor activated sprinkles that startle deer away from a particular area. You can see the limitations to such an approach, since running water to a dozen sprinkles that only protect perhaps an acre or so of growing space may not be cost or time effective.

With any options you try out, remember what you are dealing with. Deer become accustomed to sight, sound, and other such repellents quickly.  So, they need rotated, moved, and otherwise switched around often to remain effective.

The effectiveness of some deer repellent devices, such as ultrasonic noise machines, is debated. “Ultrasonic devices are often sold to repel wildlife, including deer. The principle of them is that they emit sounds at wavelengths animals can hear (above 20 kilohertz), but people can't. The only problem with deer is that they hear in a different range, from two to six kilohertz, so studies have shown them not to be effective against deer. (Yes, scientists even have done hearing tests on deer.)” Perhaps manufacturers have figured this out and newer models are more effective. Request third party and field trial results before you buy!

Sacrifice patches

Another approach we have taken to dealing with deer involves planting distraction or sacrifice plantings. At first, we did this along the lower side of our main growing area. We put in rows of sweet potatoes whose sole purpose was to act as a sacrifice patch for any deer that made it over the fencing. This year, we plan to put such patches far away from our main growing space (about 100+ yards). These will hopefully keep the deer away from our main growing areas. Any sweet potatoes that do make it will then become food for our pigs, who will be rotated through the patch in the fall.

Sacrifice patches coupled with hunting permits could be a promising way to attract nuisance deer to an easy to dispatch location on a farm, similar to how hunters plant plots of crops for deer or use feeders to keep their interest in a particular spot strong. . But such an approach in some states needs legislative change and support to make removing the deer efficient and effective for the farms involved.

A hunting and permit system in need of change?

In some areas, it is very hard to hunt deer out of season. In some states, even if you are allowed, the law imposes what, in my view, are senseless limitations. For instance, in our home state, a deer taken out of season must be discarded/destroyed. The animal cannot be butchered, even to donate to charity. This kind of waste makes little sense. Why not let out of season hunting count towards a person’s bag limit? Or set up a system that allows such food to be redirected to those in need while protecting farm crops at the same time?

It is clear deer are an increasing problem, and not just for farmers. Car accidents involving deer are also increasing. 

Deer carry ticks and are part of a number of disease cycles that the public are concerned about as well.

Getting ahead of the curve

Farmer’s should take advantage of these problems and concerns and position themselves and legislative change that gives them more flexibility to deal with deer issues as part of the solution - providing more tools to farmers to control and prevent deer damage while also selling it’s side benefits - greater public safety on our roadways and help in suppressing diseases that are negatively impacting more and more Americans.

If nothing changes, over the next five to ten years, not only will we face increasing crop damage from deer across the nation, we will also see increased rates of vehicular incidents with associated increases in insurance rates and other costs. Farmers can play a vital, central role in the solution to all these problems - helping keep deer populations in check.

How are you handling deer damage for your operation? What is your state’s legal environment like for dealing with deer and other four legged crop pests? Have you had success with fences or dogs to protect your farm investments?