Farmers using a cover-crop seeder developed by Penn State agricultural scientists may eventually need only a single trip across the field to accomplish what today takes them three passes and several pieces of equipment.
Farmers are increasingly interested in growing cover crops, but the time, cost and late autumn harvest of corn and other crops often limit their use, said Gregory Roth, professor of agronomy at Penn State.
The seeder can help farmers, especially within small operations, save time and money by condensing multiple tasks into one trip through a so-called no-till farmed field. It also would allow farmers to seed fields that lacked cover crops owing to late-season and cost concerns.
‘It can do three things in one pass,’ said Roth. ‘It can seed the cover crop, add fertiliser and spray a herbicide to kill emerged weeds.’
Unlike ploughing, the no-till farming method only disturbs the ground a minimal amount when seeds are planted, improving the soil and preventing erosion. Cover crops play an important role in reducing run-off and helping to build organic material in the soil during the autumn and the spring.
A tractor pulls the seeder through the cornfield rows using a sensor to guide the device between them. The device has several blades that lightly till the ground between the cornrows, creating a planting swath. The seeds drop onto the soil and a follow-up roller packs the seed into place. At the same time, the machine strategically applies a fertiliser and a herbicide.
According to Roth, the best time to use the device is six weeks after the corn is planted. If the cover crop is planted too early, it can compete with the corn plants. If it is planted too late, the corn crop may be too competitive for the cover crop to grow.
A single pass through a field costs the farmer approximately $10 (£6) an acre, added Roth. By saving one to two trips through the fields, farmers could save $10–20 per acre.
The researchers tested the seeder last summer in three studies. In each of the studies, the crop seeder was successful in establishing cover crops without any impact on corn yields.
The researchers tested three cover crops — annual ryegrass, red clover and white clover. They also tested a mixture of ryegrass and clover. As ryegrass and clover can prevent soil erosion and serve as a natural source of nitrogen, farmers may not need to purchase as much fertiliser.
The researchers said they were pleased with the results of the first tests, but added that they had more work to do to perfect the seeder. But if the seeder is marketed, the researchers believe that it will be inexpensive enough for use on small farms.