1. Winter canola: Its place in Kansas cropping systems 1 2. Eastern gamagrass production in Kansas 4 3. Common bunt and seed treatments for wheat 5

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1 Number 44 August 11, Winter canola: Its place in Kansas cropping systems 1 2. Eastern gamagrass production in Kansas 4 3. Common bunt and seed treatments for wheat 5 1. Winter canola: Its place in Kansas cropping systems Winter canola typically is grown in Kansas south of I-70 and west of the Flint Hills. Early spring freezes have restricted canola production north of I-70. The thin, shallow clay-pan soils of southeast Kansas often have hindered fall stand establishment resulting in an increased risk of winterkill. However, the improved winterhardiness of today s cultivars should allow winter canola to be grown anywhere in the state. Winter canola s growing season is very similar to winter wheat, and is best suited for dryland and limited irrigation production. One of its primary uses is as a rotation crop with winter wheat. By planting winter canola, producers can control some of the winter annual grasses that can become a problem in continuous wheat fields. Cheat, downy brome, volunteer rye, Italian ryegrass, and other grassy weeds can be controlled with Select 2 EC or Assure II herbicides in conventional canola, or with Roundup if using a Roundup Ready variety. Wheat yields following canola have reportedly been 10 to 20 percent higher than following wheat, although there have been no university studies to verify this claim. Canola yields have averaged approximately 1,500 to 2,000 pounds per acre in Kansas in recent years. In a very good year, producers could expect as much as 3,000 pounds per acre on dryland. During the severe drought of 2006, dryland canola yields were closer to 600 to 1,300 pounds per acre, according to the National Winter Canola Variety Trial results. Under limited irrigation, yields have been as high as 4,000 pounds per acre. Canola prices in Kansas ranged from about 8.5 to 10 cents per pound this year. Transportation costs are high in Kansas and Oklahoma because of the lack of nearby crushing facilities. Prices exceeded 13 cents per pound in 2006 in North Dakota, where 1

2 there are several nearby crushing facilities and transportation costs are low. There are tentative plans for a crushing facility in Kiowa. Three problems were evident in the 2006 winter canola crop in Kansas and Oklahoma: * Stand establishment and maintenance in no-till, * A late flush of new growth just before harvest, and * Aphid damage. The difficulty producers face in establishing a good stand when planting canola no-till is likely related to its small seed size and the need for shallow planting. It can be difficult to place the seed at shallow depths with good seed-to-soil contact through heavy residue. Another concern with no-till is that the crown of the plant may develop on top of heavy residue rather than at the soil surface. This results in a higher risk of winterkill. Some notill producers experienced a gradual decline in their canola stands beginning in November and continuing through the winter months, likely due to loss of plants with exposed crowns. It is recommended that producers clear what residue they can from the seed row when planting no-till. The flush of green regrowth that occurred at maturity in 2006 often was stimulated by late rains after a prolonged dry period during flowering and seed fill. This regrowth began flowering when the main seed pods were near maturity, causing problems at harvest. Under these conditions, it may be possible to spray with a desiccant such as glyphosate or swath the crop to aid in drydown. Green regrowth has been an uncommon occurrence the past several years. The third problem of 2006 was aphid pressure. Left uncontrolled, aphids can completely devastate a canola stand in the late fall, winter, or early spring. An insecticidal seed treatment such as Helix Extra or Prosper 400 is recommended to control aphids through January, especially in years with unusually warm winters. An ongoing concern with canola in Kansas and Oklahoma is shattering. Swathing the crop when 60 to 75 percent of the seeds are black and seed moisture is 40 percent can help reduce shattering losses. Despite these concerns, canola is a very good rotation option for winter wheat. The profit potential of canola has been compared to winter wheat, based on typical crop budgets. The following chart summarizes the profit potential comparisons, using grain-only figures for both crops. More details can be found at: Canola Yield Necessary for Canola to Break Even with Wheat Yields of 30, 45, and 60 bu/acre at Various Prices Wheat Yield (bu/a) Breakeven Canola Yield (lbs/acre) Wheat Price ($/bu) $3.25 $4.00 $4.75 Canola Price $0.10/lb 2

3 30 1,340 1,650 1, ,780 2,240 2, ,220 2,830 3,440 Canola Price $0.08/lb 30 1,850 2,270 2, ,450 3,080 3, ,050 3,890 4,740 In general, the production costs for winter canola (both conventional and Roundup Ready) are estimated to be about $35 to $40 per acre higher than for wheat in the crop budgets developed by Oklahoma State University, so the gross return for canola needs to be that much higher for the two crops to be comparable. The greatest value of winter canola may be in allowing producers in continuous wheat systems to rotate to a broadleaf winter crop with similar profit potential, and gain control of winter annual grassy weeds. This value does not appear in either K-State s or Oklahoma State s budgets. When comparing the profit potential of canola and wheat, income from grazing is not taken into account. Canola can be grazed, but grazing pressure must be watched carefully because the growing point of canola is always above ground. Producers should not let cattle overgraze canola if they intend to take the crop to seed. For the upcoming growing season, four conventional winter canola varieties are available from K-State and certified seed growers across the state. Croplan Genetics offers one conventional variety and two conventional hybrids. Monsanto offers two Roundup Ready varieties. The strengths of winter canola in Kansas cropping systems include: * Excellent crop for rotating with wheat. * Markets are developing across Kansas. * Profit potential is similar to wheat. The weaknesses of winter canola in Kansas cropping systems include: * Shattering at harvest. * Aphids can become a serious problem and must be controlled. * Establishing a good stand can be more difficult than for wheat. * Consistency of winter survival across Kansas. Next week, we will discuss seeding rates, fertilizer rates, planting dates, and other production practices for winter canola in Kansas. -- Mike Stamm, Canola Breeder (Kansas State University and Oklahoma State University) mjstamm@ksu.edu 3

4 -- Kraig Roozeboom, Cropping Systems Specialist 2. Eastern gamagrass production in Kansas Eastern gamagrass is a native, warm-season bunch grass adapted to deep soils with good moisture relationships. The tall, clump-type grass has thick, knotty rhizomes that can form plants 2 to 4 feet in diameter. Eastern gamagrass is rarely found in native rangeland grazed season-long, but can be found on sub-irrigated sites throughout Kansas. It is highly palatable and forage production and quality are higher than other native species. Eastern gamagrass is currently being promoted for tame pasture, hay meadow, or seed production. Under irrigation and high fertility, forage production has reached as high as 10 tons per acre. Production on non-irrigated situations varies. Only one named cultivar, Pete, has been officially released to commercial seed companies. All seed released is from this source, which was released in Historically, eastern gamagrass has been considered difficult to establish. Seed dormancy, seeding date, stand establishment, and grazing management are the major barriers. Stand establishment. Dormant seed should be planted ½ to 1 inch deep between December 1 and March 1 at a rate of 6 to 8 pounds per acre of pure live seed (PLS). Within the first year after harvest, seed dormancy can greatly limit seedling emergence. The process of stratification, which is chilling, soaking, and treating with a fungicide, can improve the problem. Stratified seed cannot be allowed to dry before planting and must be kept chilled if not planted immediately after purchase. Since it is moist, it may heat and destroy the germination. Stratified seed should be planted ½ to 1 inch deep between March 15 and May 30 at a rate of 6 to 8 pounds per acre of PLS. The ideal row spacing for Eastern gamagrass is 10 inches wide or less. Traditionally, stands have been planted 30 to 60 inches apart, which results in large clumps up to 3 feet across with large bare spaces between plants. The rough fields are difficult to harvest and hard on harvest equipment. There currently aren t any herbicides labeled for eastern gamagrass weed control, but frequent clipping and flash grazing can control weed growth. Once established, a prescribed burn will enhance grass production and weed management. The burn should occur when new spring growth is about 1 inch tall, which is prior to the usual time to burn native rangeland. 4

5 Management. Fertilizer should be applied in late April according to soil test results. Eastern gamagrass can be cut for hay or grazed. When cut for hay, the first harvest should occur about June 15 to 20 and the second cutting six weeks later. A 6- to 8-inch stubble should be left at both cuttings. About 50 pounds of actual nitrogen can be applied in mid-april and again after the first cutting. This will produce 3 to 4 tons of hay with 12 percent crude protein. Eastern gamagrass should not be grazed continuously, or grazed shorter than 8 to 10 inches. Successful grazing should include a 7 to 9 paddock pasture system with each paddock grazed 2 to 5 days. The paddocks should be allowed at least a 30-day rest period before restocking. A five-year research project in Oklahoma produced an average daily gain of 2.03 pounds in cattle grazing a paddock system between May 9 and August 25. Eastern Gamagrass Forage Yields Under Two Harvest Systems: Southeast Agricultural Research Center Cutting regimen (2-cut) N rate (lbs/acre 1-cut 1st 2nd Total tons/acre (23 percent moisture) Gary Kilgore, Southeast Area Crops and Soils Specialist gkilgore@ksu.edu 3. Common bunt and seed treatments for wheat (Editor s note: The following is an article from the June 9, 2006 issue of Plant Disease Alert, from Extension Plant Pathology at K-State. I am including it in this newsletter both as a reminder of the situation and because there are several recipients of this newsletter who may not have seen the Plant Disease Alert. Steve Watson, Agronomy e- Update editor) In the Plant Pathology Department, we have received several calls and s regarding a problem with some wheat in north central Kansas. Two obvious symptoms present include large clouds of black dust that occur while the wheat is being combined and a fishy smell to the wheat. The problem has been reported in an area roughly from Washington to Beloit and south to Lindsborg. The problem has been identified as common bunt. The following is an excerpt of some information provided by Bob Bowden, USDA wheat pathologist. 5

6 There are several types of smut that can attack wheat: loose smut, flag smut, common bunt (stinking smut), dwarf bunt, and Karnal bunt. Loose smut replaces the grain and chaff with black powdery spores. You see it around flowering time. After that, the spores all fall off or blow away and all you have left is a bare rachis. It is not known to have a bad smell. Flag smut causes grayish-black stripes on the leaves, and it is very rare in Kansas. It also is not known to have a bad smell Common bunt, dwarf bunt, and Karnal bunt can all produce a fishy smell. Dwarf bunt and Karnal bunt are not known to occur in Kansas. Common bunt causes the entire kernel to be replaced by bunt spores; however the outer pericarp usually remains intact. The result is a dark, puffy looking kernel called a bunt ball. These often survive the combining process and get into the harvested grain. Common bunt can easily be diagnosed by viewing the spores microscopically. Question: How severe does common bunt have to be in a field to create an odor problem? Answer: Probably around 1% of the plants infected would start to cause a stink. Question: What conditions may have existed to magnify the odor humid weather, late harvest? Answer: Common bunt is primarily seed-borne in Kansas. The most likely cause of the problem is continually planting bin-run seed without using a seed treatment. You need to either get new seed regularly or use a seed treatment fungicide. In very, very dry summers, the disease can also be soilborne. Either way, seed treatments should still work. Question: What seed treatments (currently available) are effective in the control of common bunt? Answer: Almost every commercial seed treatment should work on common bunt. Vitavax, Enhance, Dividend, and Raxil, are all good to excellent. A new Fact Sheet on common bunt will be available shortly on the Plant Pathology web site: -- Doug Jardine, Extension Plant Pathology State Leader jardine@ksu.edu These e-updates are a regular weekly item from K-State Extension Agronomy. All of the Research and Extension faculty in Agronomy will be involved as sources from time to time. If you have any questions or suggestions for topics you'd like to have us address in 6

7 this weekly update, contact Jim Shroyer, Research and Extension Crop Production Specialist and State Extension Agronomy Leader