What are annual, biennial & perennial deer forages?
By Matt Tarr, Whitetail Stewards, Inc.
What do the terms annual, biennial, and perennial mean?
The terms annual, biennial, and perennial refer to the length of time a plant needs to complete its life cycle. Specifically, the terms refer to the length of time it takes a plant to germinate, grow, produce seeds and die.
Why are these terms important?
It is important to know whether the forages you are planting are annuals, biennials or perennials. Most importantly, the life cycle of your forages determines how often you will have to replant them. There are also some situations when you might want to select to plant an annual forage instead of a perennial, and vise-versa.
The difference between annuals, biennials, and perennials
The following is a short description of the differences between annual, biennial and perennial forages.
Annuals
Annuals are plants that require only one growing season to complete their life cycle. At the end of one growing season they die. This means that you must replant these forages each year if you want to keep them in your food plots. Some annuals can be encouraged to reseed themselves through proper management of the food plot. This management may include mowing, fertilizing, and disking, and will depending on the forage species you have planted.
Winter and summer annuals
Annual forages are divided into two groups, winter annuals and summer annuals. The following are some general characteristics of each.
Winter annuals:
are planted in late summer or early-fall
begin growing soon after planting
go dormant in winter
begin growing again in early spring
die by mid-summer
Summer annuals:
are planted in early spring through early summer
begin growing soon after planting
produce most of their forage in summer
die in fall or early winter
The specific period when a given annual can be planted and expected to grow is somewhat flexible. This planting period is determined by whether the annual is a cool-season forage or warm-season forage, as well as the region in which it is being planted.
Benefits of annuals
Annual forages offer a number of benefits in deer food plots. One benefit is that annuals germinate quickly after they are planted. In some forage species, growth occurs within a few days of planting. This means that these forages will begin producing usable food for deer very quickly. This quick growth makes annuals especially useful in fall-planted hunting food plots or for providing an early spring food source to deer. Additionally, this quick growth makes annuals useful if you need to stabilize exposed soils quickly (e.g., logging road, log landing, newly created food plot).
Biennials
Biennials are forages that require two growing seasons to complete their life cycle. They are most often planted in spring, grow throughout summer and fall, go dormant in winter, and begin growing again the following spring. At the end of their second summer they produce seeds and then die. This means these forages will need to be replanted every two years. Very few food plot forages are true biennials. Yellow sweetclover is an example of a biennial forage sometimes planted in deer food plots.
Perennials
Perennials are plants that require at least 3 years to complete their growing cycle. This means that you can get multiple years of forage production from a single planting. They do this by developing specialized root systems that allow them to regenerate from their roots after the leaves and stems of the plant die at the end of the growing season. The number of season you will get from a single planting depends of the specific forage species, how well you maintain the food plot, and the region you are in.
Benefits of perennials
By far, the biggest benefit of planting perennial forages is that you can get more than one year of good forage production from a single planting. This will allow you to keep your seed and labor costs lower than required on annual plots, which must usually be disked and often replanted each year.
Which forages are annuals and which are perennials?
