Winter canola offers Texas and Oklahoma farmers a viable alternative to wheat as a rotation crop or as a moisture-efficient option. But to get the best benefit from canola, producers have to be willing to ramp up management a bit.
Josh Bushong, Oklahoma State University Extension specialist, offered a fairly comprehensive list of production practices canola producers should consider during the Red River Crops Conference in Childress, Texas.
Canola prices are higher than wheat, he says. “Typically, wheat brings 65 percent the price of canola. But producers also have more input costs.”
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It needs about 10 inches of moisture to make a crop but 16 inches to 22 inches to hit optimum yields. “The last few years canola has been living from rain to rain.” Moisture conditions this winter, for the most part, are much improved.
Canola produces a long taproot, probing as far as 66 inches into the soil, “searching for moisture.” Canola responds to adequate water. Each inch adds 3.5 bushels (175 pounds) to canola yield. “We need about 0.3 inch per day during peak use, flowering and pod fill,” Bushong says. “Water stress has a lot to do with winter survival.”
Producers may lose stands in the winter when freezing temperatures occur in concert with moisture stress. “Adequate water makes a big difference in freeze survival,” he notes.
Competition from other vegetation also hurts canola’s chances. Mesquite that encroaches close to a canola field will pull water away from the canola and the canola goes dormant.
Planting date is crucial to winter survival, especially in a dry winter. “The plant lives off the tap root in dry conditions so earlier planting (and early growth) provides a better opportunity to maintain the stand.”
Soil crusting may restrict emergence and stand. The best remedy may be to do nothing. “A light harrow or rotary hoe may do more harm than good,” Bushong says. “Just wait and see if the seedlings can push through. Every case is different. We’ve seen varietal differences in the ability to push through crusted soils. Look for bigger seed and vigor. Those hybrids also produce a faster stand, a bigger plant and a better chance to survive the winter.”
Some varieties are more freeze tolerant than others. “Larger-seeded hybrids with better vigor also have higher yield potential,” Bushong says.
Getting the stand started also makes a difference. He recommends a firm seedbed and good seed-to-soil contact. Minimum-till or strip-till production also works, but residue management is critical for consistent stands. Otherwise, growers may expect delayed maturity and thin stands.
“We need a clean planting row, so we should be aggressive with residue management on the planter to get better, faster emergence, better vigor and better early growth.”
The clean furrow of strip-till planting “offers better odds for a good stand.”
Canola takes more nitrogen than wheat, about 25 percent more, Bushong says. “We need some nitrogen applied in the fall for early growth, but not all; topdress the rest later. Adequate fertility improves potential to survive winter stress. Also, look at phosphorus and potassium levels before considering the possibility of other nutrient deficiencies. Consider pre-plant applications of phosphorus and potassium.”
A pH level should be above 5. Low 5s and upper 4s “could be too low. With 5s we get into better soils. Lower levels may result in some stand loss and stunted plants.
Several pests may injure canola. “Seed treatments are good options for aphid control but not for worms,” says Bushong.
Diamondback moths may get into canola fields but damage is “mostly cosmetic if the crop is on good land and is growing well. It can do some damage if plants are smaller and under more stress. An insecticide application may be necessary.”
Several aphids feed on canola. The turnip aphid comes on in the fall and also early spring. The green peach aphid is a fall-and late-spring pest, and the cabbage aphid comes in late spring. “Variegated cutworm may do damage during the reproductive stage and can cause rapid pod destruction in late spring.”
Fake chinch bugs may come on prior to harvest.
Weeds can also be troublesome, especially if Roundup (for Roundup Ready varieties) goes on late. Early competition could result in yield loss.
“We see some diseases but no devastating effects. Moisture level is a factor.”
Winter survival, overcoming freezes, especially, is crucial for canola producers. An early start helps plants survive fall freezes. “Temperature swings to freezing in the fall may thin stands. Soil moisture is a big factor in the plant’s ability to recover from cold snaps. The growth stage also makes a difference. A good tap root helps canola survive these early freezes,” Bushong says.
“Canola plants need moisture to come out of winter stress.” Spring rains may also spur new growth that will be vulnerable to spring cold snaps.
A plant with the crown close to the ground handles freezing temperatures better. “Freeze damage varies with moisture availability. Damage may also spur disease issues.”
Heat can be a factor. “Temperatures above 86 degrees may result in pollen sterilization. High winds make it worse and may even blow flowers off the plant.”
Shatter losses can be significant at harvest. “The faster you get canola out (after proper maturity) the better.”
Bushong says canola prices are down a bit now but the Southwest has one advantage. “We will be the first canola crop to come off in the United States.”
The crop was progressing well early in the winter, some places needing another rain or two at the time. “We have a good crop out there.”
But it’s a crop that’s still subject to the ravages of winter, potential insect problems and harvest losses. Continued good management will help minimize those threats, Bushong says.