Pascual Hernandez
Pascual Hernandez

Wildlife managers pay attention to the forage value offered by plants on their property.

As such they must decide which particular browse plants should be kept or removed when brush control efforts are planned. One resource available is a Texas A&M AgriLife Extension Service publication titled “Key Food Plants For Deer In The Edwards Plateau”.

The publication lists plants from our area into the following categories: high preference, moderate preference, low preference, or least used.

Plants in the “high preference” group are usually in short supply and may even be absent from ranches because of heavy browsing by livestock and/or deer in the past. Examples include kidneywood, littleleaf leadtree, and mistletoe.

Plants in the “moderate preference” group are not as attractive to deer as plants in the high preference group, but deer eat them willingly. If plants in this group are browsed heavily in early summer, the property is probably over-stocked. Examples include bumelia, ephedra, hackberry, and redbuds.
The “low preference” group is used by deer after more desirable plants disappear from the range. Examples include catclaw acacia, flameleaf sumac, and skunkbush. In the Edwards Plateau, live oak is in this group. It is a large part of deer diets because it has green foliage all year.

The “least used” group includes a number of woody plants that are often considered invasive and undesirable and are managed to control their abundance. These plants become abundant because they are rarely browsed and thus gain a competitive advantage over the plants animals prefer to eat. Least used plants usually are protected from browsing by physical or chemical deterrents. For example, cedar has volatile oils (terpenes) that discourage browsing. Agarito has a physical defense (young leaves are tender and readily eaten, but mature agarito leaves are tough with sharp spines on the edges and are rarely eaten). Although mesquite has tough thorns, its main protection from browsing seems to be leaf chemicals.

It is known that preference for particular plants is influenced by factors such as soil type, growth stage of the plant, degree of use by herbivores, and the availability of other plants.

For example, Ephedra is considered a “moderately preferred” plant in the Edwards Plateau, but in South Texas, it is deemed as a “high preference” plant. Similarly prickly pear is considered as “least preferred” in the Edwards Plateau, and yet thought of as “moderately preferred” in South Texas. It is on account of what else is available for deer to choose from.

In a later article, we’ll discuss nutritional values of these browse species, but the publication we mentioned is a good one. If you are interested in the browse values for white-tailed deer, check it out!