Managing Cover Crops Profitably - Valley Crops Home

Sweetclover: Good Grazing, Great Green Manure
Bill Granzow taps biennial yellow and white pounds of N to the soil. He knocks back
sweetclovers to enhance soil tilth, control
persistent re-growing sweetclover crowns
erosion and prevent subsoil from becoming in the sorghum by adding 2, 4-D or Banvel
compacted. He works with a common variety to the postemerge herbicide mix.
that his father originally bought from a
• Green manure/fallow. Disk at-mid to full
neighbor.
bloom, summer fallow then plant wheat
Granzow, of Herington, Kan., produces grain again in fall.This method provides about
and runs cattle in an area midway between
120 lb. N/A, according to estimates from
Wichita and Manhattan in the east-central
Kansas State University. Disking or other
part of the state.
light tillage controls weeds that may
Granzow overseeds sweetclover into winter emerge with sufficient rainfall.
wheat in December or January at 12 to 15 • Seed crop. He windrows the plants when
lb./A using a rotary broadcaster mounted on about 50 percent of the seedpods have
his pickup. Sometimes he asks the local grain turned black, then runs the stalks through
cooperative to mix the seed with his urea
his combine.To remove all of the hulls,
fertilizer for the wheat. There’s no extra
he runs the seed through the combine a
charge for seed application. Granzow also
second or third time.
plants sweetclover at the same rate with
Despite the heavy growth in the second
March-seeded oats.
year, yellow sweetclover matures and dies
Yellow sweetclover has overgrown
back naturally.Two or more passes with his
Granzow’s wheat only when the wheat
496 International disk with smooth 21-inch
stand is thin and abnormally heavy rains delay blades on 9 inch spacings does an adequate
harvest.The minimal problem is even more job to prepare for fall planting.
rare in oats, he says.
Granzow sows sorghum following
He uses yellow sweetclover with the
sweetclover with an 800 International Cycloplanter
with small furrow openers.Another
companion wheat crop in four possible ways,
depending on what the field needs or what option would be to use a no-till planter after
other value he wants to maximize. For each, herbicide desiccation, he says.
he lets the clover grow untouched after wheat He rates fall sweetclover hay from the
harvest for the duration of the seeding year. seeding year as “acceptable forage.” He’s
Second-year options include:
aware that moldy sweetclover hay contains
• Grazing/green manure. Turn in livestock coumarin, a compound that can kill cattle, but
when the clover reaches 4 inches tall, let he’s never encountered the problem. Secondyear
yellow sweetclover makes silage at initial
them graze for several weeks, then disk
several times before planting grain sorghum. to mid-bloom stage with 16 percent protein
He feeds an anti-bloat medication to keep on a dry matter basis.“Mixed with grass hay
cattle healthy on the lush legume forage. or other silage, it makes an excellent feed,” he
• Quick green manure. Disk at least twice says, adding value to its cover crop benefits
after it has grown 3 to 4 inches, then plant and giving him farming flexiblity.
sorghum.This method contributes about 60
142 MANAGING COVER CROPS PROFITABLY