My goal on these forums is to help landowners and managers learn how to grow high yielding forages that are also high in nutritive values while at the same time lowering their inputs by improving soils through a combination of crops and rotations.
We our fortunate to have all kinds of options that if planted properly, provide top quality forage and brassicas are one of those options. In this thread we have shared the use of three short season brassicas that include rape (canola), turnips and forage radish all of which have the potential to attract and feed deer well into late fall or early winter in most states.
Because many landowners are learning and eager to understand why they might wish to include brassicas in their habitat program perhaps we should go back to the beginning and compare the merits of each alone and in combination. Each brassica species has pros and cons and within each species are varieties with different qualities and a number of hybrids.
Which one is right for you? Do you need one, two or three species? Is it necessary to plant multiple varieties? What are each plants soil improving attributes if any?
Here are some thoughts to consider to help you better decide what might be best for you and your program.
The items in the quotes are from this link:
Brassicas for ForageRape or canola is usually one of the first brassicas that deer will begin feeding on and seed is reasonable at $1 to 3 a pound. Rape can be used as a cover crop and if plowed under provide green manure but for most hunter/landowners this isn’t the reason we plant it nor a viable option. Rape does not have a long tap root so is generally not capable of breaking up hardpan nor does it have any ability to store nitrogen.
Rape is a short-season leafy brassica whose stems and leaves are ready to harvest (rotationally graze, strip graze or green chop) 90- 120 days after establishment. Plants develop a reddish tinge when ready for harvest. Rangi, Windall, Dwarf Essex, Winfred and Emerald varieties have performed satisfactorily in Penn State University trials. Leave a ten-inch stubble to facilitate rapid regrowth.
Rape leaves and stems have lower protein level (14-17%) than turnips. Rapes can attain yields of 8000 lb/acre dry matter if planted during May or June. Rape can be planted as late as August 1, but with lowered potential yield if planted late. Seed at 3-4 lb/acre rate.
Please note that yields are substantially reduced if planted after August 1st and rape typically will perform best if optimum levels of NPK are achieved at a planting. Rape is a higher nitrogen user so 60-90#’s per acre will greatly enhance both yield and quality of forage.
Turnips are often the last to be grazed until deer adapt to feeding on the turnip tops although many hybrids such as Appin and Pasja are more palatable and attractive. The positive attribute about turnips is the ability to grow a large bulbous root that deer will feed on long after other crops are gone. This in effect is “stockpiling” a food source that deer can take advantage of even after heavy snows.
Turnips do have a tap root that can extend down several feet but the bulk of the root is a softball sized bulb that often pushes itself out of the ground rather then drilling deeper. This lends itself perfectly to being an easy meal once severe weather kills the tops and in most cases deer will dig thru deep snows to reach this nutritious food source.
Turnips are short-season root brassicas that provide roots, stem and leaf growth for rotational grazing or strip grazing 70 to 90 days after seeding. The leaves can be grazed from mid- September until January depending upon critical low temperatures and snow cover. Top growth generally will survive temperatures between 15-20 degrees F, while bulbs will be about 5 degrees hardier. The common purple top garden type as well as Rondo, Royal Crown and other forage varieties, yield up to 7000 lb/acre of dry matter. The tops have 17-24% crude protein while roots contain 12-15% protein. Some new forage-type turnip varieties such as All Top produce relatively more top dry matter than roots. Turnips are seeded from mid July to mid August at rate of 2-3 lb/acre and produce maximum yields approximately 90 days after seeding
Again one must understand that planting after mid August begins to severely reduce yield and since the main attribute of turnips is root production, late plantings result in little or no root production.
Turnips are also heavy nitrogen users and just as with rape require 60-90#’s of nitrogen along with proper P&K levels or they will be short and stunted and lacking in the kind of protein levels we hope for.
Turnips do have the ability to bring up some subsoil nutrients but limited by their slender tap root and the round root does little to relieve soil compaction problems. Typically turnips would not be considered high on the list of soil improving crops but they can be an essential element as a late winter food source.
Forage radishes have been bred for root growth and forage production versus oilseed production and although they have been around awhile are relatively new to many landowners as a whitetail food source.
FR tops can be upwards of 20% protein and are quite possibly the highest on the palatablity list when it comes to brassicas. They can produce up to 8000#’s per acre of biomass and up to 3700#’s below ground in their root systems. The roots are also very high in protein but because much of it is below ground do not offer the late winter food source potential that turnips do.
FR are fast growing and can be planted from late July to early September and quickly begin to provide attractive forage lasting into early winter. FR like other brassicas also will produce higher yielding better quality forage is 60-90#’s of nitrogen is applied at a planting…depending on planting dates.
FR has some advantages in regards to the shape and size of its leaf in that it is more feathery or serrated rather then broad and flat such as with rape. Planted thick enough it will indeed canopy and smother competition but at lighter rates it lends itself better to being mixed with other brassicas or in fall cereal grain plantings.
Forage radish plants are unique in that their roots can grow 2-4 feet and tap roots as much as 8 feet deep allowing them to pull up subsoil nutrients from deep into the soil. “Drilling for nutrients is somewhat like drilling for oil; it does require some energy to find more energy and while radishes will grow with no added “energy” supplying them with nitrogen allows them to drill deeper into the soil.
The process of drilling or growing this long extended root creates a hole when the root decomposes and when combined in a planting will leave the soil mellow and loose the next spring. This allows the next crop to fully extend its own roots freely to reach water and nutrients rather then having its roots crammed up against a brick wall so to speak.
The root channels allow surface water to flow in and then freezing and thawing moves the soil much like a subsoiler on a tractor only with less energy required per acre.
All of that makes forage radishes very attractive but they have yet another unique attribute that also is lacking in other brassicas. The long tap root is able to capture and store nitrogen and while it does require some N to do the “drilling” it is then able to scavenge as much as 140#’s of nitrogen per acre that will be released the following spring for the next crop via the accumulated N.
All brassicas have allelopathic chemicals that can inhibit many small seeds from germinating but forage radishes are perhaps the strongest of all brassicas in that regard. In addition to reducing weed problems they also release biotoxic compounds that also suppress bacteria, fungi, insects and nematodes that can lower crop yields.
Kale and
swedes are long season brassicas that are also attractive and useful in habitat programs but we’ll cover those another time.
Looking at the three aforementioned brassica species one can see that each has notable attributes that can make them very useful in attracting and holding whitetails in fall and early winter.
Each has pros and cons, rape has no root but it’s highly palatable and nutritious leaf makes it a great choice for early to late fall feed. It has few soil improving attributes and is a high nitrogen user.
Turnips are less attractive then rape but the roots make them a necessary component in a habitat program to provide late winter feed. It has some minor soil improving attributes and is also a high nitrogen user.
Forage radish leaves are extremely palatable and highly sought after by whitetails and do have some limited usefulness from the root that extends from the soil surface. It’s soil improving attributes are tremendous and for those with heavy clay soils it has the potential to make huge strides in ones soil and it’s ability to produce higher quality food sources for deer.
Unlike other brassicas forage radish has the added ability to capture and store nitrogen, re-releasing it to the next crop at no more more expense then that applied to rape and turnips.
Each of these three plants could be planted alone or in a mix that includes on or all three at seeding rates that are compatible with soil fertility, applied nutrients and grazing pressure. Some common sense and prudence is necessary and lighter seeding rates usually better then heavy.
Planting any of these brassicas to early will insure that they will mature and go to seed rendering them useless to whitetails and opening up a pandoras box of problems from volunteer plants the following year.
One variety of each is all that is needed but planting multiple varieties is sometimes fun and each has slightly different attributes that can help increase the overall effectiveness of your brassica plot.
Crops like clover, alfalfa and forage soybeans are some of the highest in protein and this is important for lactating does and antler development in bucks so they are usually better choices for spring and summer feed.
Brassicas however can tolerate colder temps and thus become a very important and valuable food source for late fall and early winter. Planting strips or blocks of brassicas, clover and fall cereal grains allows one to rotate crops and by following a tilled under legume such as clover, landowners can significantly reduce nitrogen inputs.
Utilizing nitrogen scavengers like forage radish and winter rye in your rotation allows nitrogen to be captured and used by the next crops while at the same time offering your whitetail herd attractive high quality forage.
If you feel brassicas have a place in your habitat program, look over the attributes of each and then decide which combination might work best for you, your deer and the soils on your land.
