IPM NEWSLETTER Update for Field Crops and Their Pests

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1 The University of Tennessee IPM NEWSLETTER Update for Field Crops and Their Pests West TN Research and Education Center 605 Airways Boulevard Jackson, TN No. 2 April 9, 2010 Past newsletters and other information can be found at UTcrops.com Bookmarks: Weed Control Insect Stuff Farm Management Announcement: Cotton Scout School - Friday, May 28 th, 8:30 AM - 1:30 PM, West TN Research & Education Center, Jackson. The school includes a go-to-the-field session after a box lunch. There is no pre-registration or fee. Weed Control Issues (Larry Steckel, Weed Specialist) Sharpen Questions. The number one call of the past ten days has been on the new herbicide Sharpen. The most often asked question about Sharpen is on the surfactant. Yes, it does perform best with 1% MSO plus 8.5 to 17 lbs AMS/100 gallons or 1.25 to 2.5% UAN (Picture right). Yes, COC is also mentioned on the label and is cheaper. However, to get the most consistent control of horseweed (marestail) across environments go with the MSO. The second most asked question on Sharpen is can I tankmix Valor with it? By the label it is allowed if it is applied more than 30 days before planting soybeans. However, there is a chance that the Valor can burn marestail too quickly and cause poor uptake of the Sharpen and reduce overall control. We have seen this in one trial here at Jackson this spring (picture right). This is just one test but it does provide a potential heads up to a problem. At this point, I would recommend that the applications be split. Sharpen + Roundup Original Max + MSO + AMS control of horseweed 6 DAA Valor + Sharpen + Roundup Original Max + MSO + AMS control of horseweed 6 DAA The one new observation this year is that the glyphosate + Sharpen tankmixes appear to be controlling ryegrass better than what we have seen with glyphosate + dicamba or 2,4-D. I am not really sure what the reason is. It could be that we did not realize just how much antagonism dicamba and 2,4-D caused glyphosate in controlling ryegrass. It could also be that the 1

2 MSO is helping the ryegrass uptake of the glyphosate. Or it could be some combination of the two. Whatever the cause I will take it. Fortunately, we have not found glyphosate-resistant (GR) ryegrass here in Tennessee yet. If we do get GR ryegrass I would not expect the glyphosate + Sharpen tankmix to be very effective. Word from my colleagues down at Stoneville, MS is that they are having major issues again this spring with GR ryegrass. ALS and Axial Resistant Ryegrass. We had some ryegrass samples taken from 5 wheat fields in the Dyersburg area screened for resistance to glyphosate, Osprey and Axial this winter. The good folks down at Stoneville, MS (Dr. Nandula) did the screening for us. The good news is that glyphosate provided complete control of all the samples. Unfortunately, that is not the case with the other two herbicides. Axial resistance was found in 4 of the 5 fields. The level of resistance to Axial ranged from 10 to 60%. Osprey resistance was found in 2 of the 5 fields. The level of Osprey resistance ranged from 20 to 60%. This is the first time we have confirmed resistance to these two herbicides in Tennessee. As quickly as resistance can spread with ryegrass we could lose Axial, Osprey and PowerFlex very quickly if we do not start using a complete program to control ryegrass. Herbicides we really have not used much before like Axiom, Sencor and Prowl H2O need to be utilized side by side with Axial, Osprey or PowerFlex to have any chance to manage ryegrass long term. Recrop Intervals After Wheat Herbicides. There are a few acres of winter wheat that look very good at this point. There are some other fields however that may be more profitable to be burned down and replanted to another crop. Knowing when and what herbicides were applied to thin wheat stands is a major consideration on a potential recrop decision. Harmony Extra XP which is used on most wheat acres in Tennessee has a 45 day plant back restriction to several row crops. Osprey and Axial the herbicides we commonly use to control ryegrass, have considerably longer recrop intervals. Below please find the recrop intervals for our commonly used herbicides in wheat: Herbicide Grain Sorghum Corn Cotton Soybean Express 45 days 45 days 45 days 45 days Harmony Extra SG 45 days 45 days 14 days 45 days Harmony Extra XP 45 days 45 days 14 days 45 days Harmony GT 0 days 0 days 45 days 0 days Osprey 10 months 12 months 90 days 90 days Axial 120 days 120 days 120 days 120 days PowerFlex 9 months 9 months 9 months 5 months Insect Considerations (Scott Stewart, IPM Specialist) Corn. As recently planted corn begins to emerge, it is important to scout fields during the first 2-3 weeks after emergence. Insecticide seed treatments such as Poncho and Cruiser reduce the risk of problems but are not foolproof, and neither provides adequate control of cutworms. This is the time when the corn is most sensitive to injury from soil and seedling pests. Determine if a uniform and adequate stand is present. If not or plants are unhealthy, a closer examination is in order to determine the cause of problems. Wheat. As should be expected, aphid populations are beginning to build, but there have been no reports of problems. Unless aphid populations are unusually high, there is little benefit to treating for aphids at this time of year. Any potential transmission of barley-yellow dwarf virus has probably already occurred. And as a general rule of thumb, virus transmission at this point impact has little impact on yield. 2

3 Cereal Leaf Beetle Adult (left) and Larva (right). Adult photo courtesy of Robert Bellm, Univ. of Illinois. We have noticed adult cereal leaf beetles in wheat fields. The larval stage is a gooey critter that stains your pants and causes injury by scraping the green tissue from the leaf surface (windowpane). Larval infestations will start becoming apparent in the next few weeks. Cereal leaf beetles are rarely a serious pest, but some fields did require treatment last year. Treatment is recommended if one larva or adult is present per stem. A number of insecticides are labeled for control. The pyrethroid insecticides are typically used and provide good control (e.g., Baythroid XL, Declare, Prolex, Karate, Warrior or Mustang Max). Boll Weevil Trapping in Post-Eradication Era. I m sure most people are aware that no boll weevils were caught in Tennessee during 2009, nor were any boll weevils caught in Missouri, Arkansas or Mississippi. Randall Crow of the Southeast Boll Weevil Eradication Foundation was kind enough to provide the following information Trapping Protocol: All boll weevil traps will be placed on a one-half mile grid. Traps will be put out beginning the first week in May. Due to the ½ mile spacing between the traps, not all cotton fields will have traps, but each field should have a trap within ½ mile. Traps will be checked on a three week cycle beginning June 6. In the event a boll weevil is captured, extensive trapping (400 ft apart around entire fields) will be implemented within one mile of capture trap. These traps will be serviced weekly for remainder of season. An additional capture within the extensive trapping area triggers an application of Malathion to this area. Treatments will continue until no further boll weevils are captured for three weeks, or the end of growing season is reached, or harvest eliminates potential food or shelter. Farm Management Update (Chuck Danehower, Area Specialist Farm Management) It is crunch time as the 2010 planting season has started. Most planting decisions have been made, but there may be a few acres still undecided. Planting conditions during the optimum planting window will dictate how much of a crop gets planted. If planting conditions are good, producers may plant a few more acres of that particular crop. If planting conditions are not favorable, then producers may wait until the next crop. This generally applies to corn and cotton acres with the default acreage being soybeans. 3

4 Spring conditions aside, there are several factors that go into making planting decisions, but the ones that seem to have the greatest impact are the following: Profitability Outlook Taking into consideration price outlook, input costs, and realistic yields, what crop will generate the greatest returns? At current prices, input costs and average Tennessee yields, soybeans, corn and cotton are in the mix. It does not take much of a change in yields or prices to favor one crop over the other. If you haven t planted cotton lately, and have the equipment to raise it, it is back to where it should be considered. In estimating costs, producers need to plan on increased weed control costs from potential problems with glyphosate resistant weeds. If that is an issue, it needs to be taken care of timely or the result will be increased costs and reduced yields. Financial Position or Available Financing As producers decide what to plant, they also have to look at their financial position as they decide on the amount of risk they can afford to take on higher cost crops like cotton and corn. Is the reward worth the additional risk? The amount a lender will finance will also have a bearing on the crop planted. Certainly, enough capital is needed to take the crop from planting to harvest. Land Owned, cash or share rent On own or cash rent ground, producers can decide on the crop that will make the most money or have the most profit potential. On share rent ground, sometimes the landowner may also have some input into what gets planted. Some of this decision should be looked at over a several year period as above average returns may offset a poor year. Rotational needs of the farm should also be considered. Rotational Needs Many farms have needed to be rotated to other crops to maintain long term viability. Current prices may allow a sound rotation without much of a drop in income. Crop Insurance Coverage Producers are looking at the revenue based crop insurance policies to set a guarantee per acre. Producers may weigh the different crop guarantees as to net returns to help decide what to plant. These are just some of the factors that producers consider. I still am a firm believer of a diversified crop mix where practical and particularly where no change in equipment is needed. If equipment changes are needed for a particular crop, then some of the advantages of that crop could be given up in increased fixed equipment costs. That is where a whole farm plan will be beneficial to determine the feasibility of operational changes. Prices are at a level where a slight change in yield and or price can favor one crop over another. It is a rare year where we have a record yield in all crops. Usually, one crop will outshine the others, and it is impossible to predict which crop it will be. From a profitability standpoint and in making cropping decisions when equipment changes are not being made, a partial budget such as below is useful. If the farm is making operational changes then a whole farm plan should be examined. This table examines the returns above variable expenses and returns above variable expenses and a 25% share land cost. If the farm is share rented, that particular share should be considered as a cost. Producers should use their own farm average yields, price 4

5 outlook, and their inputs. Looking at different yields and prices can be most useful when determining the financial risk and profit potential. The prices below are based on current fall delivery prices and what prices could be this fall. Cotton prices are expected to be stable while corn and soybean prices are expected to decline under normal growing conditions Estimated Net Returns per Acre Cotton Corn Corn Soybeans Yield 875 lbs. 120 bu. 150 bu. 40 bu. Price available 4/6/10 $.71 lb. $3.40 $3.40 $9.07 Potential price this fall $3.00 $3.00 $8.25 Revenue $621 $408 $360 $510 $450 $363 $330 Variable Cost 1 $416 $265 $323 $323 $323 $214 $214 Returns above variable $205 $143 $ 37 $187 $127 $149 $116 Land Costs 2 $155 $102 $ 90 $128 $113 $ 91 $ 83 Returns above specified costs $ 50 $ 41 ($ 53) $ 59 $14 $ 58 $ 33 1 Variable costs are seed, fertilizer, chemicals, fuel, repairs, and labor. Crop insurance is not included. 2 Land costs are based on 25% of gross revenue. Yields and prices are estimates only to be used in planning purposes. Cotton price estimate includes the loan rate plus an estimated loan equity payment and seed and hauling allowance. Producers should use their yields and prices estimates in their budgets. Technology and seed selection will vary among individual producers. This budget example assumes the following: Cotton Bt II or Wide Strike RR Flex; Corn 120 bu. RR; Corn 150 bu. Bt II RR; Soybeans - RR. A sound cropping plan should include crop diversification different crops, different varieties and rotation. Cotton should be back in the cropping program for producers who are set up to raise cotton. We don t know what crops and or prices will be the bumper crop or best price. Producers who have a successful production plan should stick to that plan at least on their core acres. That would probably leave 15% - 25% of a producer s acreage to be somewhat flexible and more dependent on conditions before planting such as fertilizer prices, commodity prices, and planting conditions. For assistance on farm planning, budgets or crop decisions, contact your local County Extension office. 5

6 The University of Tennessee is an EEO/AA/Title VI/Title IX/Section 504/ADA/ADEA institution in the provision of its education and employment programs and services. All qualified applicants will receive equal consideration for employment without regard to race, color, national origin, religion, sex, pregnancy, marital status, sexual orientation, gender identity, age, physical or mental disability, or covered veteran status. The University of Tennessee Institute of Agriculture, Agricultural Extension Service, Tim Cross, Dean. DISCLAIMER STATEMENT This publication contains pesticide recommendations that are subject to change at any time. The recommendations in this publication are provided only as a guide. It is always the pesticide applicator's responsibility, by law, to read and follow all current label directions for the specific pesticide being used. The label takes precedence over the recommendations found in this publication. Use of trade or brand names in this publication is for clarity and information; it does not imply approval of the product to the exclusion of others which may be of similar, suitable composition, nor does it guarantee or warrant the standard of the product. The author(s), The University of Tennessee, The Institute of Agriculture and the University of Tennessee Extension assume no liability resulting from the use of these recommendations. Scott D. Stewart (editor) Extension IPM Specialist 6