When it comes to your basic cool-season legume for deer forage, alfalfa (Medicago sativa) can’t be beat.
It is a perennial, but it can also be used as an annual in deer food plots, especially in more southern regions.
Alfalfa does not do well on clay soils; keep that in mind if your whitetail plot is located in such an area.
At about 19% protein and 1.35% calcium, alfalfa is especially good to supplement diets in the spring and early summer.
Alfalfa is a common forage crop used to make hay for cattle and sheep.
If there are alfalfa fields located at or near your hunting ground, be sure to factor that into your food plot location or design. Deer that are used to grazing alfalfa elsewhere may not be as tempted to try it in a new planting.
There are other legumes that are often recommended for deer food plots.
A number of these are warm-season annuals: hairy indigo, partridge pea, cowpea and deer vetch (also known as Aeschonomyne).
Of these warm-season annuals, cowpea can have good early-season forage potential for deer in some regions. A cool-season annual, Austrian winter pea, has also performed well in more southern regions.
For a fall forage legume in my part of the world, though, you almost have to go with a cool-season annual like vetch (Vicia) or birdsfoot trefoil. These can be important legume forage sources that can complement the grasses and grains in your food plot’s design. Don’t forget to properly inoculate the seed before planting.
And never plant a legume without taking a look at soybeans.
Soybeans (Glycine max) are a legume that deer love to consume. In fact, you may have acquired the right to hunt near farmland where the owners or managers are hoping your efforts will help manage deer populations that have enjoyed eating soybean a little too much!
There are two kinds of soybeans used in deer food plot plantings: soybeans used for grain production and “forage soybeans” or soybeans planted to provide green forage in the early fall. Grain soybeans can be planted from spring through the summer for deer forage, and may especially attract deer if soybeans aren’t widely grown in your area. Some varieties of soybeans have been bred to be resistant to Roundup™. If you want to utilize such varieties into a new food plot, that can potentially make weed control a lot easier.
I like soybeans best in larger food plots. Whitetail deer will keep the soybean from maturing in plantings of an acre or less, especially if there are not other soybean options nearby. Soybeans can be used as a source of winter feed, but soybean stems tend to lodge (bend/break) in the winter, making them less reliable than some of the other grains commonly used in deer food plots.
Be sure to use an inoculant when planting soybeans. Plantings in areas with nearby soybean acreage for fall and winter browsing should be made in the spring. Soybeans planted as Annual Forage legumes in fall food plots can be seeded between mid-August and mid-September. Personally, though, I prefer other fall forage options.
Some soybean varieties have been bred to be more ideally suited for forage, but many managers find that grain soybeans are suitable for late summer seeding—and in a new food plot, the “Roundup Ready” option of soybeans that can be sprayed with glyphosate may be especially attractive in the first year.