Red Clover (Trifolium pratense)

Red Clover is a tall perennial legume that is widely-adapted and establishes quickly. Depending on variety and circumstance, red clover can persist from 1 to 3 years. A good stand of red clover can annually produce 2-3 tons of dry matter/acre and fix nitrogen at 70 – 150 lbs/acre.

There are two general types of red clover commonly planted in the northern regions of the United States. Medium red clover (or double-cut) is a multi-cut clover which will recover after each cutting and is generally the best choice for under-seeding a small grain. The other common type is Mammoth red clover (also called Single Cut) which is later flowering than Medium red clover but will not recover after cutting making it a good choice for direct seeded fields that will be plowed down or cut only once a year.

Anecdotal Information:

Jefferson, WI "That Cinnamon Red Clover outgrew the nurse crop of Barley. The second crop was over 3 feet tall. The second year it yielded 10 Ton/acre. This was on tough ground where I have had a hard time growing corn and beans."

Black River Falls, WI "I do custom hay bagging and I feel that red clover is underrated production-wise. People think it's hard to dry. I cut it with a haybine, it's all the chopper can handle, and then I follow right behind with a hay conditioner. If you let it start to dry before the conditioner then more of the leaves fall off. Usually it takes about 40 acres of alfalfa to fill an 8 x 200 bag, but I've had clover do it in 18 or 19 acres."

Agronomic Basics: Red Clover

Description:

Management considerations:

• Red clover handles wetter soils, lower fertility, and lower pH better than alfalfa but is generally less winter hardy and not as drought tolerant.
  Maximum yields are obtained when soil pH is 6.0 or higher
  Produces rapid early spring growth and some varieties can produce two crops a year A good companion crop with alfalfa and/or grasses when used for haylage but can be slow to dry when making hay. Can cause bloat in livestock when grazed.
• Medium Red Clover (a.k.a. Double-Cut) is an early flowering variety used when more than one cutting is desired. Other multiple-cut varieties such as Arlington, Marathon, or Cinnamon offer improved quality, persistence and/or disease resistance.
• Can produce 70-150 lbs. of nitrogen and 2-3 tons of dry matter per acre annually.
• Mammoth red clover is a late-flowering variety and is typically grown when a single cutting of hay or a plowdown crop is desired. Berseem clover (Trifolium alexandrinum) and Crimson clover (Trifolium incarnatum L.) are summer annual clovers that can also be used as plowdowns. (See separate Agronomic Basics papers for more information on these species.)

Optimum Planting Dates:

• Red clover can be seeded from February to May or August to October. However, research in Pennsylvania has shown that total DM yield is reduced by 110 lb/ac/day when planting is delayed after August 1st.
• Most forages need at least six weeks of growth after germination to survive the winter, so allow enough time before the first killing frost for the forage to establish when fall seeding.
• Red clover can be inter-seeded into small grain stubble, soybeans, and corn later in the season for earlier establishment.
• Dormant seeding in late fall and frost seeding in early spring before the soil thaws are other options, especially for rocky fields or those that are not readily accessible to machinery. The freeze-thaw cycle will incorporate the seed into the soil.

Seeding Recommendations:

• Red clover can be established as a pure stand, with or without a companion crop, seeded with forage grass, or sod-seeded into a grass sod to improve the existing stand.
• To ensure adequate root nodulation for nitrogen fixation, red clover seed should be inoculated with Rhizobium trifolii bacteria.
• Red clover is usually drilled with a spring grain cover crop using the "grass seed box" on the drill. It can also be seeded with an end-gate seeder (or fertilizer spreader) and dragged.
• Plant about 9 lbs of seed per acre straight or 2 - 5 lbs per acre in a mix. Seed no more than ½ inches deep.
• Soil firmness and good seed-to-soil contact are essential. Minimize the amount of tillage before seeding to avoid soil moisture loss.
• Be aware of chemical restrictions when following other crops.

Fertilization: (Consider a soil test and please contact your fertilizer professional for your specific needs):

• As a legume, red clover fixes atmospheric nitrogen with Rhizobium bacteria in its root nodules so additional nitrogen fertilizer is generally not required. Be sure the seed is treated with the proper inoculant before planting. If your soil is very acidic (pH 5.5 or lower), nodulation may be reduced and extra nitrogen may be necessary.
• Forages tend to require large amounts of phosphorus and potassium. Incorporating a 20-60-20 starter fertilizer can be beneficial if your soil analysis indicates deficiencies in your soil.
• Ensuring adequate sulfur and boron levels in lighter soils can improve yields.

Weed and Disease Control:

(This is not intended as a recommendation or endorsement of any specific product but as a list of possible controls. Please contact your chemical professional for your specific needs and always read and follow label directions):

• Select fields that have relatively good weed control, as clover seedlings do not compete well with established weeds.
• Maintaining a dense, competitive forage is important in preventing weed problems.
• Regular mowing can kill or suppress annual and biennial weeds. It can also suppress perennials and help restrict their spread.
• There are few herbicide treatments available for mixed grass-legume combinations. Spot spraying may be the best option for scattered weed infestations.
• Red clover is sensitive to the soil residues of atrazine and some Group 2 herbicides.

Managing Cover Crops Profitably, 3rd Edition - Sustainable Agric. Research and Education

Fertilizing Alfalfa, Sweet Clover, Alsike Clover, Birdsfoot Trefoil, Red Clover and Grass-Legume

Intercropping Winter Cereal Grains and Red Clover - IA State University