Category Archives: Soybean

Enlist Soybean Varieties for Double-Crop Production Systems

Although it appears that we can use existing stock of labeled dicamba products (XtendiMax with Vaporgrip Technology, FeXapan, and Engenia) for Xtend soybean varieties, some may want to switch to or use Enlist varieties to control resistant or hard-to-kill weeds in their double-crop system.

Therefore, I’m listing this past year’s results of the performance of Enlist varieties from our variety tests. Note that most of maturity group (MG) 4 varieties. I tested no late-5 or 6 varieties.

Again, the varieties that you have already selected are likely the best-performing ones for your fields; therefore, I do not recommend changing unless you need the Enlist system to control weeds in certain fields.

Note that relative yield is the yield relative to all varieties tested within a relative maturity group (e.g., early-4, late-4, early-5, etc.). Relative yield of 105 means that the variety yielded 5% greater than the average of the entire test.

Should Court Ruling on Dicamba Affect My Seed Choice for Double-Crop Soybean?

The court ruling yesterday has given a devastating blow to farmers that are depending on the Roundup Ready 2 Xtend herbicide program for their soybean. There seems to be much discussion regarding clarification of this ruling, including when the ruling can take effect and a possible “existing stocks” provision.

Until the ambiguity around the decision is clarified, it’s worth thinking about seed choice. Assuming there is little that can be done about soybean already planted and growing other than alter your postemergence tank-mixes, you may have an opportunity to switch varieties for the upcoming double-crop soybean planting.

First and most important, do not change your variety selection if you have weeds that can be controlled without the addition of labeled dicamba products (Enginia, FeXapan, Xtendimax) to your herbicide program. The varieties that your have already selected are most likely to be best for your farm and will maximize your yield.

However, if you must add dicamba to your glyphosate to kill glyphosate-resistant marestail (hopefully you’ll take care of this weed before you plant), Palmer amaranth, or common ragweed, then you have some options with Liberty-Link, Enlist, Liberty-Link GT27, or a few other varieties that have stacked the GT and LL traits.

Like all herbicide-resistant traits, there are good varieties and there are some that don’t yield so well. I suggest that you refer to our Virginia Soybean Performance Tests 2019 or other good private and public resources to see how these have performed.

Seeding Rates for Late-Planted Soybean

The cool and wetter weather earlier in the month has delayed some soybean planting into June. In addition, some cotton growers have switched to soybean due to the same reason. The question that came to me often this week was “Should I increase my seeding rate?”

In general, our research has not found a dramatic yield response to more seed per acre until mid-June. This largely reflects the lack of decrease in yield due to late planting dates until about the same time. If planted by the first week of June, the soybean usually has time to build a canopy great enough to capture most of the light by flowering, and does not need the extra plants.

However, I usually recommend that you begin increasing seeding rates by about 20,000 seed per week beginning the first of June.

Therefore, I would suggest the following:

This week (June 1-6): 120,000 – 140,000 seed/acre

June 7-13: 140,000-160,000 seed/acre

June 14-20: 160,000-180,000 seed/acre

June 21-27: 180,000-220,000 seed/acre

On your better soils or with later maturing varieties, use the lower seeding rate. On your less-productive soils or with earlier varieties, use the higher rate. This will insure that you you have enough leaf area to maximize the yield for those planting date.

Will the cold weather harm my soybean this weekend?

The weather reports of near-freezing temperatures in some parts of Virginia has many concerned about their wheat, corn, emerged and non-emerged soybean. I’m one of them, but we must try to be optimistic about this threat.

My weather apps seem to indicate lows in the lower 30’s in some of most northern and western growing areas on Friday and Saturday nights. This is never good, especially in May. A frost may burn off some leaves if the air remains calm, but a slight breeze during the night can keep the air temperature surrounding the plants above freezing, and in-turn the soybean plant above freezing. And as long as the temperatures don’t drop below freezing for an extended period of time, I think that our soybean will be O.K.

Why do I say this? Usually, it will take air temperatures of 28 F or less to cause permanent damage. Why is this? First, the soil temperatures are warm, in the 50’s and 60’s and the soil will not warm as fast as the air. The air nearest to the soil won’t be as cold due to this; there will be a buffer area. Even if temperatures do get down to 31-32 F, plant cells will not freeze because they contain solutes, which lowers the freezing point of the tissues. For a more thorough explanation of freeze damage to soybean, I recommend this article on the University of Wisconsin’s Cool Bean website.

Just in case, we do have some soybean damage, Purdue University has an excellent article on the subject for corn and soybean, Symptoms of Low Temperature Injury to Corn and Soybean, which include some good photos of injury. The photos show likely seedling soybean survival and death examples. If our soybean have several leaves (V1-V2) and there are some out there, it’ll take very cold temperature to freeze the entire plant. Even if frost burns the leaves off, the growing points in the nodes of these leaves will likely survive and regenerate a new stem, leading to a bushier but healthy plant. But, we can worry about that next week.

The seed that are in the ground will survive. Again, the soil temperature will not drop dramatically with the cold weather. Still, soil temperatures in the 50’s is not warm. You’ll need a fungicide seed treatment protecting them. No seed treatment? We will have to wait and see. For more details, see my last article, Soybean Planting Tips for Cool Weather

Should you stop planting? We are not. I have a planter in the field today. But my seed are treated with a fungicide. But neither do you need to be in such a hurry. We generally don’t see a drastic yield decrease until planting is delayed after June.

Soybean Planting Tips for Cool Weather

It looks as if we have come out of the unusually warm pattern we experienced during late-March thru early-April and fallen back into a cooler one. I’ve watched unusually warm soil temperatures fall rapidly during that period. Although long-term weather forecasts are speculative, it appears that the next week or so will be cooler-than-average. Below are the GFS (U.S.) and European model predictions thru next Thursday. Although today (Thursday) is very warm (& wet), notice that both models are showing below-average temperatures.

Temperature anomaly predictions from 4/29 – 5/9, 2020. Screen captured 4/29.

These low temperatures are also predicted to persist thru mid-May, as shown below.

Temperature anomaly predictions from 4/29 – 5/14, 2020. Screen captured 4/29

Keep in mind that the predictability of these models are quite low past 1 week, so this could change substantially. Still, we are dealing with some relatively cool soils and that need to affect our planting decisions once things dry up.

When soils are cool, we must get the plants up and out of the ground as soon as possible. The longer a sprouted seed is in the ground, the more likely it will be infected with numerous seedling diseases. We must always strive for rapid emergence.

Before we get into too big of a hurry to plant, we must recognize that yields will not decrease drastically for over a month. Although the date when such a decline takes place will vary with the year, my data and experience indicates that this date will not occur to the first week of June. Depending on the number of acres you need to plant, you may not need to get in that big of a hurry. If the same 2-week pattern of cold then warm periods continue, I expect to see a warm-up and warmer soils by the second week of May.

If you must plant into cool soils, I suggest that you use fungicide-treated soybean seed. This will provide some protection if the seed does remain in the soil for an extended period. Below is a table that Dr. Hillary Mehl used this winter listing the effectiveness of several active ingredients with diseases that commonly occur in Virginia. Rhizoctonia and Fusarium have traditionally been our most troublesome. Pythium can also raise it’s head occasionally. Note that only one of these treatments listed are good on sudden death syndrome (SDS), but there is now at least one other product available . I caution that nematodes are often involved with SDS, so additional measures will likely be needed to fully manage that disease.

E=excellent; VG=very good; G=good; F=fair; P=poor; NR=not rated
1 Products may vary in efficacy against different Fusarium and Pythium species.
2 Areas with mefenoxam or metalaxyl insensitive populations may see less efficacy with these products.
3 Listed seed treatments do not have efficacy against Fusarium virguliforme, causal agent of sudden death syndrome

Finally, don’t plant the seed too deep. 3/4 to 1 inch deep is enough. Planting deeper will delay emergence.

Full-Season Soybean Planting Dates, Maturity Groups, Seeding Rates, and Seed Depth

Best Planting Dates & Maturity Groups (MG). If you’ve seen some of my presentations in the past, the best maturity groups will largely depend on location, but also on field productivity. Still, we cannot talk about maturity groups without a discussion on planting date, as they influence each other. Here are some general full-season guidelines:

Planting Date x Relative Maturity Experiment in Caroline County, VA, 2019

Planting Date. On average, there is little advantage, although no disadvantage, to planting in April if using adapted varieties. My data indicate that late-MG 4s and early 5’s are generally the best choice at both planting dates. But note my comments below regarding field productivity.

Location and Maturity Group. On average and most consistently, late-MG 4 and early- to mid-MG 5 varieties have yielded more than other relative maturities when planted in May in most of Virginia. Exceptions are the Northern Piedmont and Eastern Shore. In the Northern Piedmont, late-3s through late-4s yield more than 5s. On the Eastern Shore, early- and mid-4s appear to have the advantage.

Note that these comment are based on relative maturity and planting date studies over the last 3 years and from 10 years of variety test data. This does not mean that you will see similar results every year on every field. There are always exceptions, including the following.

Early planting dates and maturity groups work best on the most productive field. By planting early with an earlier-than-adapted relative maturity will place the most critical time of soybean growth and development, the pod and seed stages, earlier in the year. We generally experience more water and heat stress earlier in the summer; therefore, a more productive field/better soil type will better tolerate the stress (and better take advantage of the longer days).

Later planting dates and later maturity groups work best on less productive soils. By planting later (up to the first week of June) and with later maturity groups (mid- to late-5s), we can avoid the most stressful time of the year, placing the critical pod and seed development into a less stressful time of the year.

Full-Season Seeding Rates: In general, 100,000 to 140,000 seed/acre (assuming at least 75% emergence) is enough to maximize soybean yield when planted in April and May. I’ve even maximized yield with less seed when early-season growth is good. All we are trying to do is grow enough leaves to get 90 to 95% light interception by early pod fill (R3).

A more detailed analysis of my data however revealed that under relatively low-yielding conditions (less than 35 bushels/acre), we need the greater seeding rates. And the lower rates sufficed under higher yielding conditions. Others have found the same thing in the Midwest and South America. What does this mean as far as adjusting your seeding rates?

First, on historically poor-yielding land, use 130,000 to 140,000 seed/acre. On historically better-yielding land, you can reduce that rate down to 100,000 to 110,000.

Note that the later you plant, as you approach June, greater seeding rates will more likely insure maximum yields.

Also note that plant emergence may be less when planted on cold, wet soils; therefore, increase the seeding rate by 10% or so.

Seed Depth. My philosophy on seed depth is plant into moisture at a depth that will give you the best and fastest emergence. Note that the longer the soybean is in the ground, the more likely it will be affected by a seedling disease. I usually recommend 1 inch deep to the bottom of the seed. Under cool and moist soils, plant as shallow as 1/2 to 3/4 inch deep. This will hasten emergence.

Once the soil warms up, you can plant deeper since germination and emergence will take place faster. But, try not to plant over 1.5 inches deep, especially in April or May. Only do so if the soil is very warm and there is little moisture in the top 1 to 1.5 inches.

Herbicide Resistant Weeds Workshops

CANCELLED! Due to Virginia Tech’s response to COVID-19 and out of concern for everyone, we are cancelling all of these workshops. We will reschedule after field season in Nov. or Dec.

Topics:

Common ragweed infesting a soybean field.
  • Herbicide Resistance- What is it and how did we get here?
  • Creating Effective Herbicide Plans
  • Integrated Weed Management of Palmer amaranth, common ragweed, and horseweed/marestail
  • Local Perspective on Weed Management
  • Putting It All Together: Creating a Weed Management Plan

CCA credits will be offered

Free lunch to start or end the program!

If you are a person with a disability and desire any assistive devices, services or other accommodations to participate in this activity, please contact the Extension office listed above or TDD* during business hours of 8:00 a.m. and 5:00 p.m. to discuss accommodations 5 days prior to the event. *TDD number is (800) 828-1120.

Virginia Cooperative Extension programs and employment are open to all, regardless of age, color, disability, gender, gender identity, gender expression, national origin, political affiliation, race, religion, sexual orientation, genetic information, veteran status, or any other basis protected by law. An equal opportunity/affirmative action employer.

Northern Neck Crops Conference – Warsaw, VA

The 2020 Northern Neck Crops Conference will be held Thursday, Jan. 16 at the Cobham Park Baptist Church, 13829 History Land Hwy Route 3, Warsaw, VA 22572. This year’s conference will include pesticide certification training, updates from FSA, NRCS, and SWCD, and several Specialists and Agents from Virginia Cooperative Extension that will cover a wide variety of topics. We look forward to seeing your there for a great day of learning and interaction with the experts. Lunch will be provided. Agenda detail are below.

Full Attendance to the conference has been approved for Private Pesticide Applicator Recertification in Category 90 & 91, and Commercial Categories 1A, 10, and 60.  The conference has also been approved for 1.0 Virginia Nutrient Management CEU and 4.0 CCA-CEU credits.

9:00 – 9:05           Welcome – Trent Jones, VCE – Northumberland & Lancaster

9:05 – 9:50           Using Cover Crops for Weed Control – Michael Flessner, VCE – Weed Science Specialist

9:50 – 10:35        Market Update Robert Harper, Virginia Farm Bureau -Grain Division Manager

10:35 – 10:40      Irrigation Resources – Julie Shortridge, VCE – Biological Systems Engineering Specialist

10:40 – 10:55      BREAK – Please visit with our sponsors!

10:55 -11:40       IPM Updates – Sally Taylor, VCE – Entomology Specialist

11:40 – 12:35      Weathering the Storm: How to Cultivate a Productive Mindset – Jeremy Daubert, VCE – Rockbridge County

12:35 – 1:15         LUNCH

1:15 – 1:20           Program Updates – Scott Hammond, NRCS – Soil Conservationist

1:20 – 1:25           Program Updates – Brandon Dillistin, NNSWCD – District Technical Manager

1:25 – 2:15           Corn and Small Grain Production Update – Wade Thomason, VCE – Grains Specialist

2:15 – 2:30           Break & Evaluations

2:30 – 3:00           Legal Updates – Robert Christian, Pesticide Investigator – VDACS

3:00 – 3:30           Safety Updates – Trent Jones & Stephanie Romelczyk, VCE – Northern Neck

3:30 – 3:40           Wrap Up & Paperwork

2020 Five County Agricultural Conference – King William, VA

The 2020 Five County Agricultural Conference will be held Wednesday, Jan. 15 at the King William Ruritan Club Building, 156 Ruritan Lane, King William, Virginia 23086. This year’s conference will include pesticide certification training, updates from FSA, NRCS, and SWCD, several Specialists and Agents from Virginia Cooperative Extension that will cover a wide variety of topics, and precision agriculture round-table discussion. In addition, you will be able to get your dicamba herbicide certification with training being offered by Don Cline of BASF. We look forward to seeing your there for a great day of learning and interaction with the experts. Lunch will be provided. Agenda detail are below.

Full Attendance to the conference has been approved for Private Pesticide Applicator Recertification in Category 90 and Commercial Categories 1A, 10, and 60.  The conference has also been approved for 1.5 Virginia Nutrient Management CEU, 2.5 Integrated Pest Management and 1.5 Crop Management CCA-CEU credits.

7:45 a.m.             Registration

8:15 a.m.             Grain Market Update, Robert Harper, Manager, Virginia Farm Bureau Grain Division

8:45 a.m.             Corn Update and Hybrid Selection – Dr. Wade Thomason

9:15 a.m.             Break

9:30 am.              Soybean basics and Soybean Variety Selection- Dr. David Holshouser, Extension Soybean Agronomist

10:00 a.m.           Crop Fertility and Fertilizers – Dr. Hunter Frame

10:30 a.m.           Precision Ag Discussion

11:45 a.m.            Cooperating Agencies (FSA, NRCS, and SWCD)

12:30 p.m.          Sponsored Lunch (Participants not seeking pesticide applicator recertification or Dicamba Certification are welcome

 to adjourn following lunch)

1:15 p.m.             Dicamba Certification – Don Cline, BASF Crop Protection

1:45 p.m.             Legal Update – Robert Christian, VDACS Pesticide Investigator

2:15 p.m.             Spill Response Activity – Robbie Longest/Mike Broaddus, Extension Agents, ANR, Essex and Caroline

3:00 p.m.             Wrap up paperwork and adjourn

2020 Four Rivers Agricultural Conference – Providence Forge, VA

The 2020 Four Rivers Agricultural Conference will be held Tuesday, Jan. 14 at Providence Forge Recreation Center: 9900 Carriage Rd, Providence Forge, 23140. This year’s conference will include pesticide certification training, several Specialists and Agents from Virginia Cooperative Extension that will cover a wide variety of topics, and others. In addition, you will be able to get your dicamba herbicide certification with training being offered by Don Cline of BASF. We look forward to seeing your there for a great day of learning and interaction with the experts. Lunch will be provided. Agenda detail are below.

Full Attendance to the conference has been approved for Private Pesticide Applicator Recertification in Category 90 and Commercial Categories 1A, 10, and 60.  The conference has also been approved for 2.5 Virginia Nutrient Management CEU and 2.0 Contact hours for DCR Conservation Planner Re-Certification

9:00        Registration Opens/Meet with Vendors

9:30        Welcome

9:35        Controlling your Drops highlighting dicamba and glyphosate– Laura Maxey-Nay, Hanover Ag Agent

10:00     Pesticide Training – droplet size/playdough- Ed Olsen, Henrico Ag Agent

10:30     Pesticide Legal Update – Robert Christian, VDACS

11:00     2nd round of registration for those not needing pesticide recertification credit

11:15     Dicamba Certification – Don Cline, BASF

12:15     Sponsored Lunch/Meet with Vendors

1:00        Agency updates

1:15        Grain Market Update- Robert Harper, Manager, Virginia Farm Bureau Grain Division

1:45        What I learned from Argentina Agriculture, pest control and nutrient management –Paul Davis

2:05        Corn Update and Hybrid Selection, Dr. Wade Thomason, Extension Grain Agronomist

2:35        Break (visit with sponsors)

2:50        Positioning Your Full-Season Soybean for Maximum Yields, Dr. David Holshouser, Extension Soybean Agronomist

3:20        Making insect management decisions now by purchasing seed for next season, Sally Taylor, Extension Grain Entomologist

3:50       Nematode Panel, various specialists will discuss current nematode control practices.

4:50       Adjourn and paperwork