Cover Thickets

Creation of cover thickets is recommended for properties lacking briar patches and clumps of shrubs or young trees. Good cover thickets are 1\4 acre or less in size and consist of plants such as blackberry, sumac, wild plum, dogwood, and cedar or pine trees. These and similar plants provide valuable protection for wildlife from strong winds, sleet and snow if their limbs or trunks create a very dense area of woody vegetation at ground level rising to several feet above the ground. Such areas also allow easy movement of small wildlife but restrict the movement of larger predators and eliminate possible attack from above by hawks or owls.

The steps to creating a good wildlife cover thicket are simple. 1) The trees or shrubs must be planted closely together to be useful for wildlife as protection from predators and weather. If planted no further than 6 feet apart, many types of briars, shrubs and trees soon grow into a thicket. 2) The area planted as a cover thicket should be no less than 50 feet wide. Cover thickets that are too small or too narrow offer little protection for wildlife. 3) The planting pattern must be one that is easily created and maintained.

Placement

Wildlife cover thickets are needed everywhere a landowner desires to have animals such as rabbits, quail and rufous-sided towhees. Small wildlife such as these need cover thickets to be available within a maximum of 100 yards from where they are at any time. This means that in large open areas the distance between cover thickets should be no greater than 200 yards in any direction. Just creating one cover thicket on your land will help, but it may not be enough. If one cover thicket is necessary, it is likely that others may be needed in different locations. You cannot have too many cover thickets, but on most Kentucky farms, there are far too few. The ideal situation is to have cover thickets properly spaced and connected to one another by strips of grasses or shrubs (wildlife corridors*).

Planting

At the end of this article are four patterns that may be helpful in planning the location of wildlife cover thickets and positioning individual seedlings. Using one of these examples as a pattern, a cover thicket requires only 1/5 of an acre of land or less and 200 seedlings. (Note: The circular pattern requires 205 seedlings or 200 if you leave 5 out of the center to construct a brushpile* for additional cover.)

There are several things to consider when deciding which shape to use. Circular areas are simpler to mow around with a tractor than square ones. If livestock are present, cover thickets must be fenced. Square areas are easier to erect a fence around than circular ones. Sometimes the only area available for a cover thicket is a field corner. A triangular shape is most practical in that situation. Corner areas in fenced pastures require placement of additional fence along the open side to provide the necessary protection from livestock. Rectangular cover thickets are easily placed along fences or as a border between two fields. Conforming to shapes shown in the drawings is not important. Nature seldom produces wildlife habitat that is regularly shaped. You could make the lines of your planting uneven if you desire a "wilder" appearance.

Symbols X and O in each example show the use of two different species of trees and shrubs. Depending on what is needed in the area, type X may be a shrub species such as dogwood, wild plum or redbud. Type O may be evergreen trees. If thick shrub cover is what is really missing, the X’s could be dogwoods and the O’s wild plums. The possibilities are numerous. In some cases only one species may be recommended. Then you would ignore the different locations for X’s and O’s.

Placement of the same tree or shrub species in a row or in a set pattern may not create the "wild" or "natural" look many people desire. To get a more natural look, randomly mix the species while planting. It is a good idea, however, if planting shrubs and taller trees together in a cover thicket to plant the shorter shrub species on the outside of the planting and the taller trees in the inner rows. (Example, plant Virginia pine on the inside and silky dogwood in the outside rows.) This will help ensure the shorter shrubs receive necessary sunlight after the trees have grown.

Before planting, some site preparation may be necessary in order to get good survival of your seedlings. Depending on site conditions, mowing or spraying herbicide may be required. Refer to Habitat How-to: Planting Trees and Shrubs for more information on preparing a site for planting and the right way to plant seedlings.

For a completely "natural" approach, you may choose to allow an area to grow into a cover thicket without planting. This method of natural revegetation* is easy and cost-free but may take longer to achieve the desired results.

Maintenance

Maintaining a cover thicket includes protecting it from mowing and livestock. It is OK to mow up to the edge of a thicket to keep it from spreading but you certainly do not want someone to accidentally mow through it. Before mowing, mark the outside edges of your cover thicket with flags, stakes or posts to prevent accidental damage to small seedlings. If livestock are present, fences must be kept up to prevent damage to seedlings.

After a cover thicket has been planted just allow it to grow. As time goes by some additional plants may naturally show up. Plants such as blackberry, sumac and red cedar growing in your cover thicket will just improve its cover value. But, after a few years, begin to keep an eye open for the possible need for maintenance. Eventually, cover thickets outgrow their usefulness as dense vegetative cover. As shrubs and trees mature, fewer limbs remain available at ground level to serve as thick protection for wildlife from severe weather and predators. Tall trees growing in or near the cover thicket will shade out smaller vines and shrubs thus reducing the amount of thick cover. Maintenance of cover thickets will require cutting of larger trees or shrubs. You should begin by cutting out all tall tree species as they naturally begin to grow in your thicket. Depending on your area, tree species such as ash, maple and locust may eventually take over if not controlled. If the cover thicket was planted to dogwood or wild plum you may need to cut a few of the largest ones down at ground level after 8 to 10 years. Those species will quickly sprout back without replanting. If your thicket was planted into evergreen species you may also want to cut some down every couple of years. Those species will not re-sprout if cut at ground level and you should plant a new one in place of each one you cut. You may want use the cut evergreen trees as a brush pile.* (Note: There is nothing wrong with removing a couple of Christmas trees from your evergreen cover thicket each year.)

You may decide not to maintain your cover thickets at all. As they grow tall they will be used by other wildlife. However, if you allow them to grow beyond the stage of useful low-level cover, you must create new cover thickets nearby so wildlife will still have that critical habitat available to them.

Sources of shrubs and trees

The least expensive source for many of the recommended species of shrubs and trees is the Kentucky Division of Forestry (KDF). Seedlings should be ordered from KDF well in advance to assure availability. Planting (dibble) bars and planting machines (similar to tobacco setters) may be available from KDF.

Figure 1.

14 ROWS OF TREES SPACED 6' BY 6'

IS A SQUARE 78' BY 78' AND EQUALS

0.14 ACRE OR ABOUT 1/7 ACRE

96 TYPE "X" TREES

100 TYPE "O" TREES

196 TOTAL

Figure 2.

TWO SIDES HAVING 19 ROWS OF TREES AT 6' SPACINGS EQUALS A TRIANGLE

108' BY 108' BY 154' OR 1/8 ACRE.

99 TYPE "X’ TREES

X X O O O X X 90 TYPE "O"TREES

189 TOTAL

Figure 3.

A CIRCLE 96' IN DIAMETER HAVING TREES SPACED

6' BY 6' COVERS 0.17 ACRE OR ABOUT 1/6 ACRE.

100 TYPE "X" TREES

100 TYPE "O" TREES (LEAVING AN OPENING IN MIDDLE FOR BRUSHPILE)

200 TOTAL

Figure 4.

A RECTANGLE OF 20 ROWS WITH 10 TREES PER ROW SPACED 6' BY 6' MEASURES 54' BY 114' AND EQUALS 0.14 ACRE OR ABOUT 1/7 OF AN ACRE.

X X O O O O O O X X 100 TYPE "X" Trees

100 TYPE "O" Trees

X X O O O O O O X X 200 TOTAL Trees

*Related Habitat How-To references: