Summary of. Canola Production. Practices for Alaska. Charles W, Knight. Assistant Professor of Agronomy UNIVERSITY OF ALASKA JHAIRBANKS

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1 Summary of Canola Production Practices for Alaska Charles W, Knight Assistant Professor of Agronomy UNIVERSITY OF ALASKA JHAIRBANKS Agricultural and Forestry Experiment Station School of Agriculture and Land Resources Management Misc. Pub July 1991

2 Introduction Canola is a high-quality oil seed crop. Its production is rapidly expanding in the U.S. and Canada, and it has been successfully grown in the Matanuska and Xanana Valleys of Alaska, However, Alaska's growing season is short and does not leave much room for error. At the present time, canola is considered a marginal crop for Alaska and its production should only be attempted by producers with dependable equipment and the dedication to perform all operations at the proper time and in the correct manner. Canola is a particularly important oil seed crop for northern areas because day length (photoperiod) does not affect its ability to flower and produce seed. Canola seed weighs 50 pounds per bushel and a respectable yield is in the neighborhood of 30 bushels per acre. Seed from canola is crushed for its oil and meal. It contains, on an average, 43 percent oil and 57 percent meal by weight (DeClercq et al., 1989), Canola oil is a high quality, refined edible oil used in salad and cooking oil, mayonnaise, salad dressing, margarine, and shortenings, Canola meal is the residue left after the oil has been extracted from the seed, Canola meal (averaging 38 percent protein) is a high quality protein supplement used in livestock rations. Whole canola seed is sometimes used in animal diets when the canola has a reduced market quality or when transportation costs prohibit moving it to a processing facility. It is important to control animal intake of whole-seed canola or canola meal. Livestock producers should not feed canola without first consulting with a specialist in animal nutrition. The main problem experienced in canola production in interior Alaska has been late or uneven ripening, resulting in a mixture of green and mature seeds at harvest. Immature seeds that are killed by autumn frosts retain their green color and this adds an undesirable green tint to the processed oil. If more than two percent of the canola seeds are green, it will be rejected by the processor. There is no processing facility for canola in Alaska. Therefore, the harvested seed must either meet edible oil standards or be used as a local livestock feed. Canola research has been ongoing in Alaska since 1977 (Wooding et al., 1978; Knight et al., 1978), Major research emphasis has focused on management practices to ensure early and uniform ripening (i.e., to reduce the numbers of green seeds to meet edible oil standards). The following practices have been identified as important in reducing the hazards of late harvest and green seeds.

3 Production Practices Field selection: To break disease cycles, canola should not be planted on the same field more frequently than once every three years. In a crop rotation, canola should be planted on ground that has been summer fallowed the previous year (Knight 1980). Summer fallowed ground offers the following advantages over recropped ground: Weed Control: Although several herbicides have been tested for weed control in canola in Alaska (Conn and Knight, 1984), to date, none have been approved by the Environmental Protection Agency. Canola is slow to establish ground cover in early spring, therefore, clean fields are essential or weeds will take over the field. Without the use of a herbicide, the best practice is to plant on fallowed ground where weed growth has been controlled the previous year. Soil Moisture: Canola requires more moisture than small grains. Fallowed ground usually contains more soil moisture than recropped land, especially if crop residues have been maintained on the soil surface in the fallowed field or if the soil has been otherwise protected to prevent snow from blowing off the field. Early Planting: Fallowed ground usually warms up more rapidly in the spring and may be planted a few days earlier than recropped land. «Less Fertilizer: During a fallow season, organic matter decays in the soil releasing plant nutrients. Therefore, less fertilizer is required when planting on fallowed soil than when planting on recropped fields, Fertilization Time and Placement: All fertilizer should be broadcast on the soil surface, in the spring prior to planting, and incorporated with shallow tillage. Fertilizer should not be placed in the row with the seed for two reasons: 1) nitrogen fertilizer can burn the tiny seedlings causing reduced populations, and 2) phosphorus should be placed deeper in the soil than canola is normally seeded; phosphorus placed in the row with the seed remains so near the soil surface that it may be in dry soil and unavailable for plant uptake during much of the growing season (Knight and Lewis, 1986).

4 Type and Amount: A 35 bushel/acre canola crop requires nitrogen, phosphorus, potassium, and sulfur at rates of 105,46,83, and 21 pounds/acre of N, P2O5, and S, respectively (Alberta Agriculture, 1985). In many Alaskan soils, the micronutrient, boron (B), is deficient and must be supplemented at approximately one pound/acre to ensure early flowering and good seed set. Ideally, one should determine the amounts of available nutrients from a good soil sample, then adjust fertilization rates to supply those nutrients which are deficient. It is a good practice, however, to add a little extra phosphorus to make up for that fixed by the soil and held in forms unavailable to plants. Also, higher rates of phosphorus stimulate early ripening of the canola. In the absence of soil sample analysis, a normal fertilizer application for recropped land in the Tanana Valley would include a blend of the following materials per acre of soil; on summer fallowed soil the rates could be reduced by approximately 15 percent: Ib/A Fertilizer Material 100 ammonium sulfate ( ) 125 monoammonium phosphate ( ) 100 potassium chloride (0-0-60) 150 urea (46-0-0) 5 sodium tetraborate (20.2% B) Tillage Only minimum tillage should be conducted in the spring prior to planting. Spring tillage should not be more than three inches deep with the major purpose of incorporating fertilizers. Canola likes a firm seedbed. Ideally, producers would only sink into the soil to the depth of their shoe soles when walking across a canola seedbed. It may be beneficial to pull a packer behind tillage equipment to produce this firm seedbed. Planting Certified Seed: Always plant certified seed. When one considers the low seeding rate for canola, the additional cost of certified seed is well worth the difference. Always plant new seed; canola seed greater than two years old often has poor germination and produces weaker, less vigorous seedlings. Seed Treatment: Always treat the seed to prevent damage from fungus and flea

5 beetles. Canola seed is small. It is sometimes slow to germinate as a result of cold soil during early spring planting. Fungus can attack the seed before it germinates, or insects can damage the tiny seedlings as they emerge. A good seed treatment can prevent a crop failure. Variety: Select a short season variety adapted to the area. Make sure that the seed selected is a spring variety and not a winter variety, Make sure that it is a Polish type (Brassica campestris) which matures earlier and not an Argentine type (Bmssica napus) which may produce higher yields but seldom reaches maturity in Alaska. The most successful varieties in interior Alaska have been varieties adapted for the Peace River area of Canada, The variety Tobin' is currently the best known variety for Alaska. Depth: Canola should not be planted more than one-inch deep. Seed planted 3/4- inch deep in moist soil is ideal. If the seed is planted too deep, it will leaf out beneath the soil surface, then it will die without ever emerging. Seeding Rate: The current recommendation for Alaska is to plant canola at rates of eight to twelve pounds of viable seed per acre in solid stands or in rows no more that twelve inches apart. Numerous studies have shown that seeding rates varying from 2 to 20 pounds per acre have very little effect on canola yield (Lewis and Knight, 1982; Lewis and Knight, 1986). Plants spaced farther apart tend to branch out and compensate for thin stands. However, thick stands of canola ripen earlier and more uniformly than thin stands. The current recommended seeding rates for much of central Canada are from 4 to 5 pounds of viable seed per acre, but in Alaska where the length of the growing season is marginal, a heavier seeding rate helps to reduce the risk of large percentages of immature green seeds in the harvest. Planting Date: Highest yields and best quality seeds have been produced from canola planted in early May, Good crops can be produced from stands planted anywhere from April 20 through May 20. However, early plantings may suffer from spring frost injury, and late plantings may not fully mature in cool seasons. An ideal planting date would be between May 5 and May 10 (Knight and Sparrow, 1984; Sparrow and Knight, 1991). Planting Equipment: Canola is usually planted with a grain drill or a Brillion seeder. It is sometimes broadcast with a fertilizer spreader and buried with a spiketoothed harrow. The success of each type of planting equipment depends upon

6 the soil texture and the soil moisture condition. When soil moisture is adequate and the seed is not planted too deep, all three planting methods work well. A Brillion seeder has the advantage of shallow planting and leaving a good firm seedbed, but it does not bury all seed at a uniform depth, and if the soil dries out, the very shallow planted seed may be slow in germinating. If there is plenty of soil moisture or if the field can be planted directly behind the tillage equipment before the surface soil dries out, a Brillion seeder works well. If the surface soil is dry or if no rains are received for several days following planting, the most uniform stands will result from seedings made with a grain drill equipped with depth bands to ensure uniform seeding at about 3/4-inch depth and press wheels to firm the seedbed. Harvest Canola is combine harvested with the same equipment used for small grains. The combine cylinder speed should be set at about half the speed used for small grains, and the fan speed should be reduced to minimize blowing seed out the back of the combine. Care should be taken to plug all leaks or holes in the combine, trucks, grain bins, etc,, before harvesting since the seed is small and round, and it leaks out easily. Canola can be combine harvested as a standing crop, however, it is usually swathed then combined from the swath. Swathing is advantageous if there are green weeds or immature plants in the field. Swathing also reduces losses from wind blowing the plants and causing the ripened seed pods to shatter and drop the seeds onto the ground. Canola is ready to swath when the seeds contain about 35 percent moisture or when a majority of the seeds have lost their green color. The seeds will finish maturing in the swath if the temperature remains above freezing. The biggest disadvantage of swathing is that autumn rain or snow may wet the swath, and canola in the swath will dry more slowly than standing canola. It is recommended that the combine be equipped with a straw chopper and spreader to spread the crop residues uniformly over the field. Canola straw is not good for animal feed, and the straw contains chemical residues which may leach out of a concentrated windrow causing germination damage in the following crop. Drying and Storing Canola seed must be dried to approximately 10 percent moisture for safe storage. The chances of getting canola this dry in the field in Alaska are pretty slim, so drying facilities must be available. Canola spoils rapidly unless dried or kept cool by aeration.

7 It is possible to bin dry canola with air at approximately 1Q-20 F. However, air does not move through canola very fast and hot spots may form quickly promoting rapid spoilage. Heated air dryers are usually recommended. Air temperatures in excess of 110 F are not recommended, and the grain mass should be cooled down to 60 F immediately after drying. Temperatures should be checked in the storage bins every day during the first week after harvest, then once a week thereafter. If hot spots occur, recycling should begin immediately. Fall Tillage Fall tillage is not recommended following a canola crop, Canola is notorious for producing thick stands of volunteer plants in the season following a canola crop. A recent study (Sparrow et al., 1990) showed that most canola seeds left on or near the soil surface over winter do not survive. However, canola seeds buried by fall tillage then brought back to near the soil surface by spring tillage survive extremely well and may produce dense stands of volunteer canola plants. Another reason for not tilling the soil in the fall is that standing stubble helps to prevent snow from blowing from the field during the winter. The stabilized snow not only adds moisture to the soil in the spring, but it also insulates the soil from extreme cold temperatures, thus, the soil does not require as much heat to warm up the following spring. Discussion This summary of canola production practices is an amalgamation of research results from Alaska, established management practices from Canada, and observations of successes and failures in Alaskan fields. Canola is still an experimental crop in Alaska, and even if one follows all of the enclosed recommendations, there is no guarantee that an acceptable crop will be produced. Canola is perceived as a potential high-cash-value oil seed crop for Alaska's future. Over the past 14 years, it has been grown in the Tanana and Matanuska Valleys in small test plots and occasionally in larger production fields. Yield and seed quality from those fields have ranged from very good to very poor. The management practices listed are preliminary observations on "what appears to work best." Future research may change or refine these observations.

8 Literature Cited Alberta Agriculture Canola production in Alberta. Alberta Agriculture, Edmonton, Alberta. Conn, J.S. and C.W. Knight An evaluation of herbicides for broadleafweed control in rapeseed; efficacyf phytotoxicity, and soil persistence studies. University of Alaska Fairbanks, Agricultural and Forestry Experiment Station Bulletin 62. DeClercq, D.R., J.K. Daun and K.H, Tipples Quality of Western Canadian canola. Grain Research Laboratory, Canadian Grain Commission, Winnipeg, Manitoba. Crop Bulletin No Knight, C.W Rapeseed production and tillage management. In: Proceedings of the Second Agricultural Marketing Symposium, University of Alaska Fairbanks, pp Knight, C.W. and C.E. Lewis. 1986, Conservation tillage in the subarctic. Soil Tillage Res. 7: Knight, C.W, and S.D, Sparrow, 1984, Frost seeding of rapeseed. Agroborealis 16(2): Knight, C.W,, C.E. Lewis and FJ. Wooding Potential for rapeseed production in Alaska. In: Proceedings of the 2Sth Alaska Science Conference. University of Alaska Fairbanks Lewis, C.E. and C.W. Knight. 1982, Rapeseed response to seeding rate, row spacing, and nitrogen application. Agroborealis 14: Lewis, C.E. and C.W, Knight Yield response of rapeseed to row spacing and rates of seeding and N-fertilization in interior Alaska. Can. J. Plant Sci. 67:53-57, Sparrow, S.D., J.S. Conn, and C.W. Knight Canola seed survival over winter in the field in Alaska, Can, /. Plant Sci. 70: Sparrow, S.D. and C.W. Knight Frost-seeding of oilseed rape (Brassica campestris) in the subarctic. Crop Resh. (In press). Wooding, F.J., C.E. Lewis, and S.D. Sparrow An oilseed crop looks promising for interior Alaska. Agroborealis 10(1): The University of Alaska Fairbanks provides equal education and employment opportunities for all, regardless of race, color, religion, national origin, sex, age, disability, status as a Vietnam era or disabled veteran, marital status, changes in marital status, pregnancy, or parenthood pursuant to applicable state and federal laws, In order to simplify terminology,, trade names of products or equipment may have been used in this publication, No endorsement of products or firms mentioned is intended, nor is criticism implied of those not mentioned. Material appearing herein may be reprinted provided no endorsement of a commercial product is stated or implied. Please credit the researchers involved and the Agricultural and Forestry Experiment Station, University of Alaska Fairbanks, Printed on recycled papor