Canola refers to rapeseed which is LOW in erucic acid (less than 2 percent) and glucosinolates (less than 30 micromoles per gram of oil-free meal). Canola has the LOWEST percentage concentration of saturated fatty acids of eight commonly used vegetable oils. In January, 1985, the U.S. Food and Drug Administration approved the use of LOW erucic acid rapeseed for human consumption The term "Canola" is a name registered by the Western Canadian Oilseed Crushers Association. Mixtures of canola with HIGH erucic acid rapeseed, used in industrial oils, should NOT be planted in Ohio. Producers planting rapeseed need to be precise about the type they are planting, as well as how and where it will be marketed.
Canola consists of two species of the mustard family, Brassica campestris, called Polish turnip rape, and Brassica napus, known as Argentine rape. Ohio farmers should consider fall planted varieties rather than spring planted varieties because Ohio weather conditions will cause spring varieties to abort their flowers which reduces seed yields. Michigan research has shown fall planted varieties outyields spring plantings by 30-40 percent and can be directly combined (without being windrowed). Ohio farmers produced 40-50 bushel per acre in 1987-1989. Research plots have yielded over 55 bushel per acre.
Canola can be grown on most soil types, but is best suited to well drained and non-crusting loam soils. The seedbed must have a firm surface and good internal drainage.
Canola is susceptible to Sclerotinia wilt. Farmers should remember this when placing canola in their crop rotations. Other crops susceptible to this wilt are sunflower, soybean and dry beans. High moisture and lack of air movement increase the likelihood of this disease. In Canada and North Dakota, canola follows a cereal grain in the rotation. Canola plantings in a field should be at least four years apart. Additional diseases canola may have include: white rust, downy mildew and alternaria blackspot. Sugarbeets should not be planted in a rotation with Canola due to the possibility green peach aphids might transmit Beet Western Yellow Virus from canola to sugarbeets.
Because of the small seed size canola responds to good seedbed preparation. The seedbed should be reasonably firm, having moisture within one inch of the surface. Seed depth should be 3/8 - 3/4 inch. Alfalfa seeding equipment works well. Some Ohio farmers have mixed the seed in water or liquid fertilizer and sprayed it on the soil surface. A cultipacker should be used following this method of seeding. Plant 5-8 pounds of seed per acre depending upon seed size, soil conditions and planting technique. Use 7-8 pounds when broadcast seeding and less when using alfalfa seeding equipment. Successful seedings have also been made using the small seed box found on grain drills. Some broadcast plantings have died over winter due to dry soil conditions and poor seed-soil contact.
Canola's fertilizer response is similar to wheat. Twenty to thirty pounds of nitrogen should be applied prior to planting in the fall with an additional 80-100 pounds of nitrogen being applied prior to spring growth in late January or early February. Nitrogen and potassium should NOT be placed in direct contact with the seed, but should be broadcast. The spring nitrogen may need to be aerially applied to prevent damage of the small plants. Wide tire floater applicators should be avoided due to plant resulting from tire traffic breaking off the plants.
Canola seedlings are very sensitive to weed competition; therefore, it should be seeded in clean fields at narrow row spacings. This will result in an early leaf canopy which will shade or smother weed growth. Mixtures of canola with mustard and wild garlic will reduce the market value of the crop.
Canola is ripe when plants turn a straw color and seeds become dark brown (approximately July 1). Combine cylinder speed should be 1/2 - 3/4 that used for wheat. Seed moisture should be 9-10 percent for direct combining. Since canola shatters easily (1-5 bushel/acre at harvest), volunteer plants may grow following harvest and/or the next season. Many of the herbicides presently used in soybeans and corn will control volunteer canola.
Canola varieties vary about 10 days in maturity. Early maturing varieties would be advantageous for farmers interested in double cropping. Double cropping distributes labor and equipment requirements. Soybeans and sunflowers could easily be planted before July 15 and produce a reasonable crop if growing conditions were favorable. Sclerotinia would not be an anticipated problem on crops planted at this time.
Rapeseed trading, presently done in Canada, is utilized in establishing the price of canola. As canola acreage increases in the United States, one of the U.S. commodity exchanges may begin trading it. Archer Daniels Midland has crushing plants in Windsor, Canada and Atlanta, Georgia, while Central Soya and Calgene have a crushing plant in Chattanooga, Tennessee, which are processing most of the U.S. production at this time. The farm price at harvest time in 1988 was approximately $7 per 50 pound bushel. Sinca canola price is approximately 80% of soybean price the 1989 price received by farmers was less. Several Ohio companies have seed available and many elevators will purchase the harvested crop. Several companies will forward contract canola for harvest delivery.
Newly harvested seed may go thorough a "sweat." Air movement should be provided in all canola storage bins. Canola seed is small enough to pass through many bin aeration floors. Therefore, something such as nylon window screen may be needed on the bin floor and other ventilation channels. Ohio farmers should NOT plan on storing canola through the winter.
Northwest District Agronomist
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Keith L. Smith, Associate Vice President for Ag. Adm. and Director, OSU Extension.
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