Seed & Chemical
The benefits of ridge tillage are well documented
November 12, 2007 By Peter Darbishire
The benefits of ridge tillage are well documented. Though many of the growers
who adopted the system 15 to 20 years ago have either changed to another form
of reduced tillage or have decided to quit farming altogether in favour of retirement,
a few have persevered, combining ridge tillage with strip cropping. They have
done so because the system still makes perfect economic sense.
At Chatham, Ontario, Bob Stewart has grown corn and soybeans on ridges since
1990, with all his 300 acres in ridges and 15 foot strips since 1992. "I
haven't pulled a moldboard plow since 1979," he says proudly. He graduated
from a Soil Saver system to a ridge tillage system to reduce the costs of equipment,
fuel and time for fall work. He has reduced all these as well as losses from
unseen compaction, because all growing-season field traffic is controlled to
the single wheel-track of 60 inches between ridges for every 15 foot strip.
Best of all, his corn yields are consistently higher than local averages, at
200 to 205 bushels per acre. His highest two acre check was 270bu/ac (dry) in
2004. "That's a 25 to 30 percent increase over others in the area,"
he says. As well, he has improved his soils considerably. He farms sandy loam
soils, with some sharp sands and these have been turned around from what were
some of the poorest soils in the area. "Good soil life has resulted in
a reduction in soybean cyst nematodes, too," he believes. Soil organic
matter content is still increasing.
He reckons he loses three to five bushels per acre on strip soybeans by comparison
to solid block fields, though his fields still average 47bu/ac. He grows his
strips in a north-south direction and: "The west row of soybeans loses
yield as a result of being in the shadow of the adjacent corn row," he
Stewart emphasizes that the key to being successful with ridge tillage is to
have the right mind-set and to hold off from planting until the field is fit.
As no-tillers have found, this requires some patience at first. However, once
the system is set up, it allows him to make alterations, like growing white
beans in rotation on a block he has taken out of strips. "White beans need
more in-crop passes for insecticide sprays and there would be more damage by
growing them in narrow strips," he explains. "But white beans gross
as much as corn," so he will keep a 100 acre block separate from his strips
to rotate with corn and soybeans.
At the end of the day, Stewart remains a ridge till, strip farming proponent.
He believes a beginning farmer should consider it as an option because the machinery
investment is lower. For himself, he is satisfied also that it is good for agriculture
to use a conservation-friendly method.
The mechanics of ridges and strips
The first step is to set up the ridges: using a ridge hiller on bare ground
to begin. Once the system is set, ridges are rebuilt in the corn crop after
the plants have reached six to eight inches tall. Stewart uses a Hiniker six-row
ridger, fitted with wings to rebuild the ridges about six to eight inches from
ridge to valley. A second pass just before the rows close establishes the ridges
for the season.
The ridges gradually reduce in height through the corn season and soybeans
are planted in the top of the remaining ridge in year two. Corn is planted using
a group of three coulters with a 3/4in 13 wave blade, one in the centre of the
row, the other two inches off the row on each side.
Stewart plants Roundup Ready soybeans and sprays them when there is little
wind to avoid damage to adjacent non-Roundup Ready corn.
In the spring, a burndown is used over the whole field soon after the first
weeds are up.
Corn is planted into the top of the ridge without removing soil as some US
growers do. "We notice a three to five degree C temperature difference
from the valley to the ridge," says Stewart.
The centre four rows of corn in each strip are planted to achieve a population
of 32,000 plants per acre. Rows one and six are planted to 36,000, since they
receive more sunlight and have more yield potential.
Stewart applies 24lb/ac of regular MAP at planting through the insecticide
boxes of his planter to improve early root development. He applies 12gal/ac
of 28 percent UAN two inches to the side of the seedrow at planting. At the
first ridging operation, he applies 50gal/ac of 28 percent UAN through tubes
off the sides of the shares of the Hiniker ridger. Fertilizer is carried in
saddle tanks on the tractor.
All growing-season traffic uses the centre rows, at 60 inches. For harvesting,
Stewart's Case IH combine track is set at 120 inches.