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The Rural Voice, 1985-11, Page 27underseeding a forage into wheat or barley in spring and plowing it down in the fall, the nitrogen fixed can be beneficial to subsequent crops and can lower costs by reducing fertilizer requirements. The research at Centralia shows that if red clover is used as a plowdown, no nitrogen on corn is re- quired for at least one year after in order to produce a yield of 7,746 to 8,295 kg/ha (124 to 133 bu/acre). However, the yield was not quite as high as a check which received 150 kg/ha (135 lbs/acre) of nitrogen and produced 8,729 kg/ha (140 bu/acre). Similar research at Kemptville has shown that no extra nitrogen on corn is required for two years following alfalfa plowdown. "Though alfalfa has a greater abili- ty to fix nitrogen," says Forrest, "single and double -cut red clover were used at Centralia's research because of seedling vigour and its ex- tensive root system." Double -cut red clover produced more top growth in the fall and a bet- ter corn yield the subsequent year (8,295 kg/ha or 35 bu/acre) than single -cut red clover (7,746 kg/ha or 124 bu/acre). Lionel Wilder, who farms near Zurich, claims that double -cut red clover catches easier and is faster - growing than single -cut. He has used barley and wheat underseeded with red clover in his rotation program on his 1,500 -acre cash crop farm for a number of years. He also claims that about 20 to 25 lbs/acre Tess of actual nitrogen is required on his following crop of corn. Forrest believes that farmers do not take full advantage of plowdown. First, the forage should be left in the field as late into fall as possible. "Do not be over-anxious to get the plow- ing done early." Even after a heavy frost when top growth has died, the bacteria responsible for fixing nitrogen are still working. Second, because there is a tendency to underestimate the amount of fixed nitrogen available, extra fertilizer is applied unnecessarily. The purpose of the plowdown is to reduce the amount of chemical fertilizer re- quired, thereby decreasing input costs as much as possible. Research is underway to determine the quantity of applied nitrogen re- quired (if any) to increase corn yields economically in the first and second year following plowdown. The se- cond year's corn crop following plowdown had substantially lower yields when no fertilizer was applied. Of course, the amount of nitrogen required will depend on the kind of legume, condition of stand, stage of growth, subsequent crop grown, and perhaps method of tillage. "More important than the nitrogen aspect is the improvement of soil structure," says Wilder. Both he and Bill Munn, a cash -crop farmer from Mensal, who follows his plowdown with a bean crop, say that the exten- sive roots of clover loosen the soil, making breaking easier. This could decrease compaction, the number of tillage operations, and the power needed for tillage, and also increase root penetration, which influences the plants' uptake of water and nutrients. The rotation is also beneficial because it interrupts pest and disease cycles. The value of forages is hard to quantify, Forrest says, but in the long run they provide immeasurable benefits. The practice of plowdown is cost- effective and ecologically sound, two criteria necessary to progressive farm- ing today.!l HILL and HILL FARMS LIMITED at VARNA CLINFIELD (Con. 2 Stanley Twp.) We are both ready to receive your 1985 SOYBEANS • CORN 7500 bushels per hour unloaded Open 24 hr a day 5 Dryers will ensure speedy service Custom combining and trucking available YOUR "FIRST LINE SEEDS " DISTRIBUTOR Pete Rowntree 482.3191 HillAND Hill FARMS \ LIMITED Bev Hill 482-3218 vOv 1 \1BI R 14,E 25