AgSolutions Advisor. Soybeans 101: the basics of growing soybeans. July 2017

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1 AgSolutions Advisor July 2017 Soybeans 101: the basics of growing soybeans. A crash course for first-time soybean growers. Written by: Paula Halabicki More and more growers across Canada are including soybeans in their crop rotation, especially in western provinces. Besides the economic benefit of growing the high-demand crop, breeding progress has produced soybean varieties that better withstand the cooler conditions and shorter season in Western Canada. 1 Between 2016 and 2017, soybean acreage is expected to increase by 40.1% in Manitoba and % in Saskatchewan with continued expansion across the west even into Alberta. 2 However, growing a crop for the first time comes with many challenges. That s why it s important to set yourself up for success by establishing your soybean crop properly, protecting it from weeds and disease, and using strategies to manage harvest efficiently. The checklist to soybean crop establishment. Even if soybeans are a new crop for you, the essentials for proper crop establishment are similar to any other crop and scouting is at the top of that list. To make informed decisions for growing soybeans, start by scouting your fields each year and keeping track of soil conditions as well as weeds and disease. Field selection. Keeping a record of your crop rotations, problem-weed areas, and herbicide use is a helpful practice, particularly when choosing where to plant a soybean crop. Since certain herbicides have residual qualities that could be harmful to your soybeans, be sure to check that enough time has passed to safely plant them as a follow-crop. Managing nutrients. Adding soybeans into rotation with cereals, pulses and canola can decrease the risk for herbicide and fungicide resistance and improve your soil conditions. Through crop rotation, you can ensure proper fertility levels for your soybeans by managing nutrients in the crops you plant the year or two before. Regularly testing your soil is also a good practice for knowing your field s nutrient levels in order to make fertilizer application decisions. It is recommended to keep phosphate levels between ppm, potassium above 100 ppm, and to maintain adequate amounts of sulfur in the soil. 3 For proper nodulation to occur, choose fields that have nitrogen levels of less than 50lb/ac.

2 Variety selection. When it comes to selecting a soybean variety, there are many considerations in addition to yield potential: How long is your growing season and how many heat units do you receive? Early-season soybean varieties need 110 to 118 days from planting to maturity and soybeans need a minimum of 2,200 to 2,300 CHUs. 4,5 Understanding your field s specific weed and disease problems can help you choose between herbicidetolerant traits (glyphosate-tolerant, dicamba-tolerant or conventional soybeans) as well as different disease ratings. Iron deficiency chlorosis (IDC) is a major issue in wet soils with high carbonates. That s why planting IDCtolerant soybeans is a worthwhile option for fields with a higher risk of IDC. 4 Figure 1. Iron deficiency chlorosis. 6,7 For more information on varieties, Manitoba offers a variety selection tool on seedmb.ca, 8 the Government of Saskatchewan offers an online seed guide, 9 and Alberta offers a new varieties list on seed.ab.ca. 10 Inoculants. As a legume crop, the symbiotic relationship between your soybeans and nitrogen-fixing rhizobia is essential for ensuring proper nitrogen levels. That s why an inoculant is vital every time you grow soybeans not to mention an inoculant that is specific to soybeans (Bradyrhizobium japonicum). And if you re in the first cycles of growing soybeans, double inoculation on-seed and in-furrow is recommended to optimize rhizobial populations in the soil. Figure 2. Healthy nodules on soybean root. 11

3 Seed treatments. Insecticide and fungicide seed treatments protect your soybeans from pests and disease in your crop s early stages. However, your crop has a higher susceptibility to pests and disease when you plant in certain conditions. That s why using a helpful tool like the Manitoba Pulse & Soybean Growers Soybean Seed Treatment Risk Assessment is helpful to assess your risk for diseases such as fusarium, pythium and rhizoctonia or insects like wireworm and seed corn maggots. It also provides information on the pests that aren t controlled by seed treatments. 12 Seeding date. When it comes to planting soybeans, it s worth paying attention to the weather forecast. The warmer the soil temperature, the quicker the soybeans will emerge. Because it s important that soybeans imbibe warm water for successful germination, cool rains may be detrimental to germination. Ideally, the soil temperature should be consistently higher than 10ºC. Be careful not to plant too early as there is risk of frost damage if temperatures go below -2ºC. 13 Row spacing. While planting soybeans in wide rows requires a lower seeding rate, narrow rows (<15 ) often contribute to a higher-yielding crop as the dense canopy conserves moisture and suppresses weed competition. 3 However, a dense canopy can also be a prime environment for disease. That s why applying a fungicide and widening the space between plants in a row is important when disease pressure is high. Your soybeans had a good start? Don t let them down in the end. Emergence to the second trifoliate is the critical period for weed control in soybeans don t miss it. It s a crucial time to protect your crop from weeds that would otherwise compete for nutrients, water and sunlight, impacting your soybean yield potential. Applying a pre-emergent herbicide is key for giving the crop a clean start. Follow with an in-crop herbicide to control flushing weeds. Be sure to choose herbicides that target your field s specific weed issues, and follow the label for application rates and staging. Practice good weed management stewardship to prevent herbicide resistance from developing, including the use of multiple modes of effective action. Keep your eyes open for disease. Choosing the right variety is the first step to protecting your soybeans from disease, particularly soil-borne diseases such as phytophthora root rot and white mold. 3 For in-season control, apply a fungicide between early flower and full bloom (late R1 to R2) to protect your soybeans from diseases such as white mold and septoria brown spot. Make a lasting impression on weeds at harvest. For greater harvest efficiency and perennial weed control, finish the season with a pre-harvest herbicide. Best practice is to apply a pre-harvest dry down when 80 to 90% of the leaves are gone and seeds are rattling in their pods. Also check that most of the pods have changed colour, with lower pods turning brown and upper pods a yellowish-brown or grey. Soybean summary. If you re planning on growing soybeans for the first time next year, it s never too early to consider the best management practices involved in producing a successful crop. From proper crop establishment to harvest efficiency, follow the practical steps to enhance your soybean crop s growth and protect it from weeds and disease.

4 References. 1. The soybean, agriculture s jack-of-all-trades, is gaining ground across Canada. Statistics Canada. Retrieved from 2. Principal field crop areas, Statistics Canada. Retrieved from 3. Soybean production guidelines. Manitoba Pulse & Soybean Growers. Retrieved from manitobapulse.ca/wp-content/uploads/2017/05/soybean-production-guidelines-april-2017_wr.pdf. 4. Nutrient management of soybean. Top Crop Manager. Retrieved from soybeans/nutrient-management-of-soybean soybean variety evaluation guide. Manitoba Pulse & Soybean Growers. Retrieved from manitobapulse.ca/wp-content/uploads/2011/08/2016-soybean-variety-evaluation_11_24_16_wr.pdf. 6. Iron deficiency chlorosis in soybean leaf. Agriculture in Ohio. Retrieved from com/tag/manganese-deficiency/. 7. Iron deficiency chlorosis in soybean field. Farm Journal s AgPro. Retrieved from com/resource-centers/crop-fertility/phosphorus-potassium/news/possible-causes-of-yellowsoybeans html. 8. Manitoba variety selection tool. Seed Manitoba. Retrieved from 9. Varieties of grain crops Government of Saskatchewan. Retrieved from documents/20/96889-varieties%20of%20grain%20crops% pdf. 10. Find seed. Alberta Seed Guide. Retrieved from Soybean root nodules. North Dakota State University. Retrieved from Soybean seed treatment risk assessment. Manitoba Pulse & Soybean Growers. Retrieved from manitobapulse.ca/wp-content/uploads/2015/03/soybean-treatment-risk-assessment_apr-2017_wr.pdf. 13. Should you be planting soybeans? Manitoba Pulse & Soybean Growers. Retrieved from manitobapulse.ca/from-the-field/should-you-be-planting-soybeans/.

5 AgSolutions Advisor July 2017 Are you a dicamba-tolerant soybean grower? You ve got options. Breaking down your herbicide choices for dicamba-tolerant soybeans. Written by: Bryce Geisel The global demand for soybeans is rising, just like soybean production rates across Canada. 1 Soybean acreage is predicted to increase by 27.2% between 2016 and 2017 with by far the largest growth in Western Canada. 2 Not only are there more soybeans being seeded, but growers are also planting more Roundup Ready 2 Xtend dicamba-tolerant (DT) soybeans to deal with specific weed problems. What growers may not realize is that there s more flexibility in choosing a herbicide application than just dicamba alone. Back to the basics on DT soybeans. With growing herbicide resistance across Canada, diversification is crucial. Using multiple modes of effective action (MMOEA) is key for growers dealing with resistant weed issues, and the multiple-mode-of-action approach begins with crop and herbicide rotation. Since Roundup Ready 2 Xtend DT soybeans offer both glyphosate- and dicamba-tolerant traits, they give growers a broader range of choice in herbicides. Growers then have the option of applying at least two modes of action with dicamba (Group 4) plus glyphosate (Group 9). Just because a grower plants DT soybeans doesn t mean dicamba and glyphosate are their only herbicide options. In fact, using dicamba on their DT soybeans is not a must. It all depends on their farm s specific weed issues. Dicamba and stewardship go hand in hand. For growers in Western Canada, Group 2 resistance is a major issue and impacts weeds such as wild oats, wild mustard and green foxtail. 3 One of the chief problem weeds is kochia, which is resistant to Groups 2 and 9. 4 Applying a Group 4 herbicide like dicamba is a good way to control these resistant biotypes. However, when it comes to weed control, everything in moderation. Resistance to herbicides such as glyphosate have developed from the chemistry s overuse in the past. That s why being a good steward of dicamba means knowing when to use certain herbicides. And one way to determine a good herbicide choice is by keeping a record of past chemistry use for each field. For example, if a grower knows they used Group 2 and Group 9 chemistries and they didn t effectively control a broadleaf weed like kochia, they should add other herbicide groups to their rotation for a broader range of control.

6 Know the strengths of dicamba. Dealing with broadleaf weeds such as lamb s quarters, pigweed or kochia? Both dicamba and glyphosate are excellent herbicide choices. With increasing glyphosate resistance in Western Canada, an application of dicamba (such as Engenia herbicide) with its tank-mix partner glyphosate is a great combination for broadleaf-weed control especially glyphosate-resistant kochia. Although growers can apply dicamba until early flower, optimum timing is pre-plant or pre-emergence. And because dicamba is water-soluble, its residual qualities are more effective in a drier year. 5 Figure 1. Glyphosate only 5 Figure 2. Glyphosate + Dicamba 5 That s one key benefit of DT soybeans: dicamba and glyphosate are both possible herbicide options, depending on a grower s broadleaf weed issues. Because glyphosate resistance is so prevalent, however, adding a Group 14 herbicide like Heat LQ to a tank mix of dicamba and glyphosate offers an additional mode of effective action to help control Group 2- and glyphosate-resistant weeds. After all, the general rule is that three modes of action are better than two. An application of dicamba is not a requirement for DT soybeans though, and a combination of Heat LQ plus glyphosate is another available option for weed control. Like dicamba, Group 14 is most effective on broadleaf weeds. And when this pre-seed/preemerge burndown is tank mixed with glyphosate, it controls weeds such as wild buckwheat, volunteer canola and cleavers as well as glyphosate-resistant weeds like kochia. The pair not only provides better weed control, it also decreases selection pressure with a MMOEA approach. Figure 3. Dicamba + Group 14 5 And don t forget it s weaknesses. While dicamba is effective on broadleaf weeds such as kochia, it is not a good option for controlling brassica weeds. And since volunteer canola is one of the biggest problem weeds in Canada, choosing herbicides that work well on brassica weeds is essential for growers who have this issue. That s why scouting for weeds is key to choosing the right herbicides. When growers know their weed issues, they can choose the appropriate herbicides to target them.

7 Applying Viper ADV herbicide from cotyledon to 4 leaf is a great option for controlling volunteer canola in DT soybeans. Although growers also have the choice to use Group 2 herbicides such as Odyssey and Solo ADV, Viper ADV offers a Group 6 (bentazon) active ingredient in addition to Group 2. The more modes of effective action, the better. Not to mention that Viper ADV can also be tank mixed with glyphosate for a broader range of control. That s three modes of action with Viper ADV plus glyphosate Group 2, Group 6 and Group 9 active ingredients. And since Group 2 resistance is especially prominent, the Group 6 active ingredient in Viper ADV is key for getting ahead of resistant weeds. 4 Dicamba-tolerant soybeans: the main deal. Choosing the right herbicides for a grower s DT soybeans comes down to knowing which weeds they wish to control. Just because DT soybeans allow the option of applying dicamba and glyphosate doesn t mean growers are restricted to those choices. Through properly scouting their fields for weed issues and keeping a record of past herbicide use, growers can use the herbicides that would fit best in their crop protection plan. References. 1. Soybean Prices are Surging Thanks to Stunning Demand from China. CNBC. Retrieved from cnbc.com/2016/12/20/soybean-prices-are-surging-thanks-to-stunning-demand-from-china.html. 2. StatsCan Seeding Intentions: Canola and Soybean Area Increase, Less Durum. Retrieved from producer.com/2017/04/statscan-seeding-intentions-canola-and-soybean-area-increase-less-durum/. 3. Managing Weed Resistance in Western Canada. BASF. Retrieved from Related_Files/Managing_Weed_Resistance.pdf. 4. International Survey of Herbicide Resistant Weeds. Retrieved from Country.aspx. 5. Soybean School: How New Dicamba Performs in Roundup Ready 2 Xtend. Retrieved from realagriculture.com/2016/11/soybean-school-how-new-dicamba-performs-in-roundup-ready-2-xtend/. Always read and follow label directions. AgSolutions, and ENGENIA are registered trade-marks of BASF Corporation; ODYSSEY, and VIPER are registered trade-marks of BASF Agrochemical Products B.V.; HEAT, and SOLO are registered trade-marks of BASF SE; all used with permission by BASF Canada Inc BASF Canada Inc. Monsanto Company is a member of Excellence Through Stewardship (ETS). Monsanto products are commercialized in accordance with ETS Product Launch Stewardship Guidance, and in compliance with Monsanto s Policy for Commercialization of Biotechnology-Derived Plant Products in Commodity Crops. These products have been approved for import into key export markets with functioning regulatory systems. Any crop or material produced from these products can only be exported to, or used, processed or sold in countries where all necessary regulatory approvals have been granted. It is a violation of national and international law to move material containing biotech traits across boundaries into nations where import is not permitted. Growers should talk to their grain handler or product purchaser to confirm their buying position for these products. Excellence Through Stewardship is a registered trademark of Excellence Through Stewardship. ALWAYS READ AND FOLLOW PESTICIDE LABEL DIRECTIONS. Roundup Ready 2 Xtend soybeans contain genes that confer tolerance to glyphosate and dicamba. Agricultural herbicides containing glyphosate will kill crops that are not tolerant to glyphosate, and those containing dicamba will kill crops that are not tolerant to dicamba. Contact your Monsanto dealer or call the Monsanto technical support line at for recommended Roundup Ready Xtend Crop System weed control programs. Roundup 2 Xtend and Roundup Ready are registered trademarks of Monsanto Technology LLC, Monsanto Canada Inc. licensee Monsanto Canada Inc.