How to Create the 3 Types of Cover Deer Need

Arriving at Stephen F. Austin State University in July of 1973, my new job was to develop a wildlife management curriculum and research program in what then was the School of Forestry. In 1974, we officially organized the Institute for White-tailed Deer Management & Research.

I want to make clear: we were not the only scientists working on deer behavior. My colleagues and friends, Drs. Harry Jacobson, Dave Guynn and Marchinton at Mississippi State University and Auburn University, were busy pursuing information about movements and habitat preferences. A lot of this research focused on the impact of forest management on whitetails.

In eastern Texas, clear-cutting as a timber regeneration method was brand new, and hunters were not happy with seeing their favorite hunting spots denuded of vegetation. My first telemetry research (putting radios on deer) focused both on movements of bucks and their use of various habitat components, as they developed after timber harvest.

There is an ecological concept called “succession,” which is the process that takes place after there is a disturbance to an ecosystem. In this case, after the trees are removed for timber, there is pretty much bare ground. The act of cutting, dragging and hauling off trees makes quite a mess on the landscape! Yet this type of forestry is no different than taking advantage of what happens naturally in the deer woods.

Hurricanes in the South and tornadoes throughout the country can produce a landscape that is pretty much denuded of trees. Lying “sleeping” in the soil are millions of seeds that may have been there for hundreds of years, just waiting for the day when sunlight again reaches the forest floor. These early plants are appropriately called “pioneers.” They quickly re-vegetate the site, but their life is very short; since, they make it possible for other plants to replace them. That’s how it goes until saplings turn into young trees that capture the sunlight, which then creates shade and eliminates the early pioneers.

This has happened over North America for millennia, and animals have adapted to take advantage of each stage in this re-occurring process. Whitetails are an excellent example and have developed a reproductive pattern that allows them to quickly take advantage of the flush of plant growth taking place during the first years following a disturbance. In most areas, the time from the appearance of early weeds and grasses to trees over-topping and shading them out is from 7-15 years. The whitetail breeding system is capable of totally saturating their habitats in this time span!

However, disturbances occur randomly (except for timber management), without any predictability or consistency. So, deer are adapted to move about the landscape, looking for places where their needs are easily met. By the mid-1980s our research had revealed that deer need travel corridors, summer and winter bedding areas, escape cover, and forage within the “deer zone” from ground level to 4.5 feet.

We also were homing in on features such as staging areas, with their signpost rubs. One of our most important discoveries was that deer would “like” to live in an area of about 80 acres (outside the rut) in most of eastern North America, needing all the above elements present in a landscape of this size. In the absence of one or more key features, deer extend out and sometimes travel longer distances, making their home range shaped more like an ellipse than a circle.

We learned that, instead of relying on happenstance to produce these life requisites of deer, forest/wildlife management has the advantage of planning! We developed a plan for the perfect deer landscape. In the early days of even-aged timber management, foresters would clear-cut up to 300 acres, just to reduce effort. Slowly, however, foresters began to accept that cuts needed to be much smaller, as well as consideration to management activities that enhance deer life requisites. Instead of just drawing a line around a stand of timber and cutting it, we began to delineate features like Streamside Management Zones (SMZs), as well as manipulating the density of trees or plants to enhance forage and cover. It is the latter we will discuss from this point on.

There are two definitions of cover: “…a thing which lies on, over, or around something, especially in order to protect or conceal it;” or “…a physical shelter or protection sought in danger.” In wildlife management, cover is, “a habitat feature that provides shelter or protection from detection or climate for an individual animal, group or family.” There are three types of cover for deer: edge, escape, summer and winter.

Edge Cover

An edge is any place where two or more habitat types meet. An easy example is the interface between a forest and a pasture. Like most things, edges come in threes: hard, soft and internal.

A hard edge is one where there is an abrupt change from one habitat to another, Animals generally do not “like” this type of edge, because moving from one to another can draw attention — especially from a forest to a field.

A soft edge is highly preferred by animals, in that it gives the individual the benefit of concealment. If you have watched deer enter a field, they do not just run out there; rather, they stop at the edge and watch for a long time! If you also pay attention, a deer will usually select an area with a soft edge to provide concealment while it watches for danger.

An internal edge is a type of soft edge between two types of forests or brushlands. A great example is, if you walk from an upland pine forest down into a drainage, you will find a point where there is the highest species diversity, which results from an interface of bottomland species with upland species of plants.

Escape Cover

Escape cover is any vegetation that will allow a deer to flee from you or a predator for a distance of at least 50 yards, stop and then not see you or you him! So, that means that escape cover can be composed of many types of plants and structures, including hills. In Kansas, many areas are vegetated by tall prairie grasses, plum or juniper thickets. I have seen bucks literally disappear into a plum thicket no more than 50 feet in diameter! So, there is no size limitation for escape cover.

Winter Thermal Cover

Winter thermal cover is exactly what the name implies. It is a type of cover that has a dense overstory canopy that impedes snow or rain, as well as a dense understory that impedes wind flow. That’s a tall order for a habitat, since for the understory to be dense, it must receive adequate sunlight! In most cases, then, winter thermal cover has an understory that is more shade tolerant. In the South, privet or yaupon can grow at high density, both in sunlight and shade. In other regions, species such as beech, American holly, arrowwood viburnum and eastern hemlock are shade tolerant. Some pine seedlings also can be shade tolerant.

Summer Thermal Cover

Characterized by having a lower overstory density, summer thermal cover has very little understory vegetation that would impede wind flow. South pine savannas are excellent summer thermal cover, along with any other forest that constitutes a savanna. A lot of summer thermal cover areas are maintained as savannas by fire, both natural and man-caused. Others are created by the encroachment of trees into a grassland at a low density. If you walk into such a place, it is pleasantly cool, with dabbled shade.

How to Build It

The importance of winter and summer thermal covers is quiet dramatic, affecting the thermal ecology of deer. A deer that is too hot will tend to restrict its diet, while one that is cold will increase feed consumption. Then comes the question: How much of the deer landscape should be in these cover types? Normally, we prefer to have about 10 percent of the area devoted to each type of thermal cover; while edges should be encouraged whenever one habitat type changes to another. So, these features are linear, not of any specific size.

The next question is: How do we make these cover types? There are two ways to make cover; modify existing habitat to provide the need, or design and plant the area to fit the need. Obviously, it takes less time to develop a cover from an existing type of vegetation than to “build” one! In developing a management plan for a specific property, we first identify the habitat types that are present, and assign a utility to each. If there is potential for modifying an existing area, then you will need to develop a plan.

This may be thinning an existing conifer stand to open it up, then using prescribed fire or mulching to reduce the understory to produce summer thermal cover. Likewise, simply protecting a dense conifer area can produce winter thermal cover. Edges and escape cover can be developed by planting tall grasses and shrubs along the interface between two habitats for edge, or patches of the same for escape cover.

Each habitat is different, and each property presents new and unique challenges. Hopefully, this guide to identifying and creating cover will lead you on the way to landscaping your perfect whitetail oasis!

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