Overton, Texas
August 23, 2005
As gasoline prices reach for the sky, so do
fertilizer prices.
"We're at the point of such high fertilizer
prices that people are going to have to learn how to grow forage
legumes and manage them properly," said Dr. Gerald Evers,
Texas Agricultural
Experiment Station forage management expert.
Because nitrogen fertilizer production uses natural gas, its
price increase is directly linked to higher fuel costs. Prices
for other fertilizers, such as potassium, also climb as
transportation costs from mining sites to the farm are also
contributing to price increases. As with gasoline prices, the
increase has been rapid and dramatic, Evers said.
Evers noted that in mid-July nitrogen – in the form of ammonium
nitrate – was about 40 cents per pound. By mid-August, it was 48
cents per pound.
"That's a 20 percent increase in about a month, and who knows
where it's going to go next," he said.
But before they give up on fertilizing, farmers should consider
alternative sources of nitrogen, he said.
Legumes can offset high fertilizer prices because they extract
nitrogen from the air. As a bonus, legumes have a higher
nutritive value than grasses. When over-seeded on warm-season
grasses, they can extend grazing five to six weeks and lessen
the need for supplemental feeding or hay during winter months,
he said.
With adequate moisture and good management, a forage legume
such as arrowleaf clover can make from 50 to 100 pounds of
nitrogen per acre available for the summer bermudagrass pasture.
"Livestock graze the legume ... and return over 90 percent of
the nitrogen to the soil as urine and manure," Evers said.
Many producers, but not all, grow some sort of winter pasture
already. The most common winter pasture in East Texas is not a
legume but ryegrass, he said.
Arrowleaf clover used to be widely grown but fell out of
favor due to plant diseases. Arrowleaf seed was mixed with
crimson clover seed and grown widely throughout many southern
states from Texas to Georgia. By mixing the early-maturing
crimson clover and late-maturing arrowleaf, ranchers and farmers
could have forage from February through early June.
Multiple disease problems put an end to the practice. The most
prevalent and damaging of the plant viruses and fungal rot was
the bean-yellow mosaic virus.
Apache, a relatively new arrowleaf clover developed by Dr. Ray
Smith, Experiment Station legume breeder based at Overton, is
highly productive and resistant to bean yellow mosaic virus.
But before farmers and ranchers rush out to plant Apache or any
other clover, they should consider several issues, Evers said.
First is soil pH. All clovers need a minimum soil pH of 6.
Arrowleaf does better with a soil pH of 6.5 to 7, however.
As it takes four to six months to raise soil pH and pasture
legumes must be planted in October, a lime application should be
made no later than spring, he said.
A standard soil test will tell producers not only their soil pH,
but the need for any soil nutrients.
The next step is to determine which forage legume to plant. When
it comes to clovers, one size – or variety – does not fit all.
Clover species are adapted to specific soil types, and don't
perform well on others.
There are about eight types of clover adapted and available for
East Texas producers, but three most prominent ones – arrowleaf,
crimson and white clovers – are adapted to most situations,
Evers said.
Arrowleaf clovers do well on deep sandy soils. Crimson
clovers are adapted to shallow sandy soils. White clovers
are well adapted to loamy soils like those found in creek
bottoms.
The National Resource Conservation Service, a federal agency
that has offices in every county, can provide detailed soil
survey maps of any farm, Evers said.
Planting rates vary as to the type of clover used, but all
plantings should be preceded with a light disking to ensure the
seed has good soil contact. Any fertilizer called for by the
soil test should be applied at planting or after legume
seedlings emerge, he said.
Rhizobia bacteria are responsible for the nitrogen fixation in
legumes and should be applied to the clover seed before
planting. It's also possible to purchase seed already inoculated
with the bacteria, Evers said.
Farmers can use a planter or broadcast the seed. Either way,
however, it is a good idea to mix the clover seed with ryegrass
seed for two reasons. The clover seed is so small that most
planters won't have the correct setting for accurate seeding
rates. Also, ryegrass makes a great mix with clover. The
ryegrass will produce forage earlier and lessen the chance of
cattle bloating on the rich forage produced by the clover, Evers
said.
More information on planting legume forages and winter pasture
can be found on the Web site of the Texas A&M University System
Agricultural Research and Extension Center at Overton:
http://overton.tamu.edu/clover/cool/.
Agricultural producers may also contact the Texas Cooperative
Extension office in their county. |