Field Crop News

Website Address: http://fcn.agronomy.psu.edu/

February 10, 2009 Vol. 09:02

IN THIS ISSUE:

Weather Outlook
Crop Producer Conference Approaching
What’s New for Agronomic Weed Control: 2009 (continued from previous edition)
Refuge-In-A-Bag: Current Status
Public Comment Requested on 2,4-D
Early Season Wheat Assessment
Spring Soil Sampling Tips
Clover Cover Crops and Nitrogen

Weather Outlook — Paul Knight, Pennsylvania State Climatologist

The thaw will continue until Thursday. Clouds and scattered showers will dominate this warmer period with the steadiest rain expected with a cold front during Wednesday night and early Thursday. Most sections should receive a quarter inch or more. Expect one of the windier days in many months on Thursday with frequent gusts to near 40 miles an hour and some ridge tops being buffeted by 60 mile an hour winds.

Seasonably cold air will return during Thursday with snow showers in the northwest adding a few inches of new snow. Friday will be settled and chilly. A fast-moving disturbance will pass just south of the state on Saturday spreading a light to moderate snow to the southeastern two-thirds of the Commonwealth. Expect a general 2–5 inches.

The chill will deepen early next week with the next storm threat around mid-week.

On balance, despite the current warm spell, February should average near or slightly below normal temperatures. A split in the jet stream flow also portends a drier than average month. Most of the longer range guidance points to a colder and wetter than average first half to two-thirds of March with a very mild end. Also, analog forecasts indicate a higher than average chance of above normal rainfall in the July-August period.

Crop Producer Conference Approaching—Greg Roth, Grain Crop Management Specialist

The second annual Professional Crop Producers Conference is just around the corner. The organizing team has done a great job this year of pulling together some interesting topics. Here’s a few that are on my list to check out at this year’s conference.

Dr. Elwyn Taylor from Iowa State is the nationally acclaimed ag meteorologist will provide the 2009 Weather Outlook. He has been tracking the La Nina this winter and will likely update us on its potential and effects on corn yield projections for this summer.

Market Trends for 2009 and Beyond by Jody Lawrence from Strategic Trading Advisors in Franklin, TN. Jodi comes with high regards from our PA Corn Growers Association and I like many of us, am interested in where the corn marketed is headed. Last year our speaker on commodities markets predicted the late season market collapse.

Tracy Blackmer from the Iowa Soybean Association will discuss N management tactics. I visited Tracy this fall and they have an incredible on farm testing program, including work with the stalk nitrate test on corn in fields right here in PA! I am interested to see how we can utilize the test more in PA to cut corn production costs on dairy farms.

I’m also looking forward to hearing our producers discuss intensive double cropping strategies that work and how they foresee their profitability in this yearâ€™s economic climate.

I am also interested in hearing Ray McCormick discuss habitat development on hunting leases. Ray is a conservation oriented farmer from southern Indiana managing a 2200 acre farm along with 1000 acres of woodlands and wetlands for wildlife. This is an opportunity area for agronomists, conservationists and input suppliers around the Keystone State.

And finally, I am looking forward to learning more about some of our emerging soybean diseases from Don Hershman from the University of Kentucky. He is one of the leading soybean pathologists in the U.S. and understands many of the issues we have here in PA.

This is my list. There are many other great presentations. I look forward to seeing many of you there this year. The Conference is set for February 17-18, 2009 at The Penn Stater Hotel in State College, PA. Register today at conferences.cas.psu.edu or call 877-778-2937.

What’s New for Agronomic Weed Control: 2009 - Soybeans, Forage and Pasture — Dwight Lingenfelter and Bill Curran, PSU Weed Science

Soybean

Authority First 70DF and Sonic 70DF (FMC/Dow AgroSciences) are preemergence herbicides combining sulfentrazone (Authority) and cloransulam (FirstRate) for residual, annual broadleaf control. In RR soybeans, apply 3 oz/A Authority First or Sonic pre followed by glyphosate post. In conventional soybeans, apply 6.45 – 8 oz/A. If used in a total pre program, Authority First or Sonic will need to be tank mixed with an appropriate herbicide to control grassy weeds and nutsedge. They can also be used as a fall burndown application in front of soybeans.

Authority Assist 4L (FMC) is a preemergence herbicide containing sulfentrazone (Authority) and imazethapyr (Pursuit). It has activity on small seeded broadleaves as well as some annual grasses. The sulfentrazone component provides excellent preemergence control of pigweed, lambsquarter, morningglory and good control on smartweed and eastern black nightshade. The addition of imazethapyr will increase control on velvetleaf, foxtail, and panicum. Apply Authority Assist from 45 days before planting to 3 days after planting at 6 to 12 fl oz/A depending on soil texture and organic matter. It can be used in a sequential pre followed by post herbicide program.

Authority MTZ 40DF (FMC) is a preemergence herbicide containing sulfentrazone (Authority) and metribuzin (Sencor) to control many annual broadleaves. In a planned pre followed by post treatment in RR soybeans, apply 10 oz/A pre followed by glyphosate post. Authority MTZ can also be applied as a fall burndown application prior to spring planting of soybean or corn.

Envive 41.3WDG (DuPont) is a spring-applied, preemergence, herbicide premix that includes chlorimuron (Classic), flumioxazin (Valor), and thifensulfuron (Harmony SG). Envive is designed to provide some burndown and residual weed control when applied two weeds before planting up to three days after planting (before soybean emergence). It can be applied at 2.5 – 5.25 oz/A (plus necessary adjuvants) tank mixed with other burndown herbicides. Envive may be followed by an appropriate post herbicide to control any escapes.

Ignite 280 2.34SL (Bayer CropScience), formerly known as Liberty, is a new higher-load formulation of glufosinate. Ignite 280 is a post, broadspectrum herbicide that controls many annual broadleaf and grassy weeds and provides some suppression to biennials and perennials. Since it is a contact herbicide, it is weaker on perennials compared to glyphosate, and requires uniform spray coverage to achieve consistent weed control. Warm temperatures, high humidity, and bright sunlight improve the performance of Ignite. It does not have residual activity and will not control weeds not yet emerged. Ignite can be used on all glufosinate resistant (LibertyLink) crops and for burndown situations. A pre application or a post application with a residual product may be required for broader spectrum and extended control in problematic fields. The use of soil residual herbicides before crop emergence can reduce the number of post applications required or provide a larger window for later season control. The typical use rate is 22 to 29 fl oz Ignite 280/A; include ammonium sulfate (AMS) at 3 lb/A to the spray solution (use only 1.5 lb/A if temperatures are expected to exceed 85°F). For more consistent lambsquarters and velvetleaf control apply between dawn and 2 hours before sunset. Ignite 280 can be applied post at 22 fl oz/A in LL soybean from emergence up to but not including the bloom stage. If using sequential applications make sure they are at least 10 to 14 days apart and do not apply more than 44 fl oz Ignite/A/growing season. Ignite 280 and the LL system will be marketed as an alternative to a Roundup Ready (glyphosate resistant) system. It allows rotating herbicide modes of action to reduce the potential of developing glyphosate resistance biotypes of weeds. Glufosinate can be slightly less effective on grasses such as yellow foxtail, johnsongrass, quackgrass, shattercane, and barnyardgrass, but is more effective on some of the broadleaf weeds such as annual morningglory, eastern black nightshade, and smartweed. Although weed size is important with glyphosate, timing is more crucial with Ignite and spray applications should be made when weeds are 4 to 6 inches tall. Liberty will not longer be produced. Ignite 280 supplies will be in short supply for 2009.

Valor XLT 40.3WDG (Valent) is similar to Envive but does not contain the thifensulfuron component, only flumioxazin (Valor) and chlorimuron (Classic). It is labeled for fall or spring burndown or pre treatment in soybeans at the 2.5 – 5 oz/A rate.

Prefix 5.3EC (Syngenta) is a preemergence, herbicide premix that includes s-metolachlor (Dual Magnum) and fomesafen (Reflex) for annual grass, nutsedge, and broadleaf control in soybeans and snap beans. Prefix at 2 – 3 pt/A can be used in conventional or RR soybean systems.

FORAGE, PASTURE and/or CR(E)P

Chateau 51WDG (Valent) contains flumioxazin and is the same ingredient found in Valor. Chateau controls several annual broadleaves and claims suppression on certain annual grasses. Apply 2 to 4 oz to established alfalfa with 6 inches or less of regrowth for preemergence control of certain weeds. Do not apply within 25 days of harvest or grazing. Application with paraquat can be used for winter annuals prior to the winter dormant period. Do not apply to mixed alfalfa-grass stands.

Cimarron Plus 63WDG (DuPont) contains metsulfuron (Cimarron) and chlorsulfuron (Glean) and controls many broadleaf weeds in grass pastures and CR(E)P lands. Cimarron Plus may be applied at 0.125 to 1.25 oz/A to many native grass species (switchgrass, bluestems, grama grass, etc.) and other pasture grasses (orchardgrass, smooth brome, etc.). Do not use on timothy or Matua bromegrass, and Cimarron Plus may injure ryegrass and fescue species. Refer to label for additional use guidelines and restrictions. Cimarron Plus will take the place of Cimarron. Cimarron 60DF is being phased out. There are several generic metsulfuron-only products still available.

Milestone and ForeFront: manure and plant residue issues. Milestone and ForeFront contain aminopyralid and provide effective broadleaf weed control in grass pastures. However, recently issues with herbicide residues in manure and plant residues have caused some problems. Keep in mind, as the label states: Do not rotate to any crop within one year following treatment, or to any broadleaf crop until an adequately sensitive field bioassay shows that the aminopyralid level in soil will not adversely affect that broadleaf crop. Do not use aminopyralid-treated plant residues, or manure from animals that have consumed forage or hay from treated areas, as compost or mulch in areas where susceptible broadleaf crops may be grown. When using these products it is important to consider what is going to be done with the site, manure, or plant clippings after application. Manure from animals that have fed on forage or hay harvested from aminopyralid-treated areas should be spread on the pasture. In general, grass clippings or wood chips (from trees, shrubs), etc. that have been treated with aminopyralid should not be used as compost or mulch in vegetable or ornamental gardens. Also, if planning to move livestock to areas with aminopyralid-sensitive species (e.g., clover, alfalfa, trefoil), any livestock that are grazing in aminopyralid-treated areas should then be allowed to graze/feed for 3 days on an untreated pasture/forage. The reason: ingested aminopyralid passes through the animal in urine and manure and can damage sensitive plants.

Chaparral - pending approval (Dow AgroSciences) is a premix of aminopyralid (Milestone) and metsulfuron (formerly Cimarron) that controls many broadleaf weeds at low use rates (2 – 3.3 oz/A). Besides thistles, ragweed, horsenettle, ironweed, and bedstraw, the combination of metsulfuron and aminopyralid improves control of certain species such as mustards, spiny amaranth, wild carrot, buttercup, jimsonweed, plantain, brambles, and multiflora rose. Initially, Dow plans to launch this product in 2009 for use in pastures and rangelands in the western and southern parts of the US. It is still uncertain if and when Chaparral will be labeled for use in pastures in Pennsylvania and the northeast US areas. Until then, a similar mixture can be obtained by simply tank-mixing Milestone or ForeFront with metsulfuron.

Refuge-In-A-Bag: Current Status — John Tooker, PSU Entomology Specialist

Many of you are probably aware that Pioneer-Hi Bred has a proposal into the Environmental Protection Agency (EPA) seeking approval of the “refuge-in-bag” approach to insect resistance management (IRM). Current refuge protocols for Bt corn require growers to have 20% of their acreage as non-Bt corn. This non-Bt acreage is an IRM tactic aimed at preventing or delaying development of resistance to Bt traits by maintain populations of pest insects (corn rootworms and/or European corn borer and other lepidopterans) that are susceptible to Bt toxin. These susceptible individuals can then mate with any potentially resistant individuals emerging from Bt fields and their offspring should be susceptible to Bt corn, thereby reducing the likelihood that resistance traits will spread in the population.

Pioneer’s “refuge-in-bag” product is Optimum® AcreMax™. As proposed, it will be a seed mix of rootworm Bt corn and non-Bt corn, with the non-Bt corn being 5% or less of the total seeds in the bag (for a news release announcing the product last spring see: http://www.seedquest.com/News/releases/2008/march/21945.htm). For rootworms, there would be no additional refuge requirements beyond the susceptible seeds included in the bag, but growers would still have to be mindful of the corn borer refuge requirements. The rootworm trait in Optimum® AcreMax™ is marketed as Herculex® RW and Herculex® XTRA and was developed jointly by Pioneer and Dow AgroSciences.

Interestingly, at a recent meeting I attended on the topic with other corn entomologists, it was evident that Dow AgroSciences does not support Pioneer’s “refuge-in-bag” proposal as submitted to the EPA, feeling that the low refuge requirements and seed mix jeopardize the Bt technology and could even hasten the development of resistance in rootworm. Toward the end of February, EPA will hold its Scientific Advisory Panel (SAP) addressing the proposal. With some opposition to the proposal, the recommendation that will emerge from the SAP is not clear, but it promises to be interesting! More detailed information on the SAP and some of the documents that have been submitted for review are available online.

Public Comment Requested on 2,4-D by February 23, 2009 — Bill Curran, Weed Science

In the December 24 Federal Register, EPA requested public comment on a petition from the Natural Resources Defense Council (NRDC) to revoke all tolerances and cancel all pesticide registrations for the herbicide 2,4-D. As you are aware, this herbicide is used on a variety of crop, turfgrass, aquatic, and noncrop situations across the country and is an important tool for broadleaf weed control.

The petitioner, NRDC, claims that EPA cannot make a finding that there is a reasonable certainty of no harm from dietary residues of 2,4-D and, therefore, that the Agency must revoke all tolerances established under section 408 of FFDCA, as amended by FQPA.

As a part of the petition, NRDC claims that the Agency did not consider the full spectrum of potential human health effects associated with 2,4-D in connection with EPA's reassessment of the existing 2,4-D tolerances, and EPA’s environmental risk assessment including:

Information on the endocrine disrupting effects of 2,4-D.
Information on the neurotoxicity related to 2,4-D exposure.
Information that products containing 2,4-D are mutagenic.
Data showing that dermal absorption of 2,4-D is enhanced by alcohol consumption, sunscreen, and DEET which the EPA’s exposure assessment failed to include.
Information about adverse developmental effects at doses below those included in EPA’s risk assessment for exposure of infants to 2,4- D in breast milk.

You may submit your comments directly to the EPA on this proposed action. Comments may be submitted via www.regulations.gov to docket EPA-HQ-OPP-2008-0877 and are due on or before February 23, 2009. You may use this Web site.

Source: Federal Register: December 24, 2008 (Volume 73, Number 248).

The NRDC petition is in Docket ID No. EPA-HQ-OPP-2008-0877.

Risk assessment and related documents for this pesticide can be found under docket ID number EPA-HQ-OPP-2004-0167.

Early Season Wheat Assessment — John Rowehl-Extension Educator, York County

If the weather cooperates and you can get out into some wheat fields this month to look at the stand you have, there are some decisions you can make about how to manage it. This is most important for fields that got planted late or had minimal growth last fall.

First determine the number of plants per square foot as follows. Take a yardstick and lay it along a row. Count the number of plants in the three-foot length. Repeat this at several random locations that represent the field condition and determine the average. Multiply this number by 4 and then divide by the number that is your row width. For example, 40 plants (per 3 ft), × 4 / 7 = 23 plants per square foot. Twenty to thirty (20-30) plants per square foot is considered adequate for maximum yield.

Plants/sq ft	Yield Potential (%)
30–35	100
22–28	100
18–21	90–95
15–18	75–80
12–14	60–70

If the number of plants per square foot is less than 12–14, consider replanting to another crop.

Determining the number of tillers can also be helpful. Tillers are secondary stems that branch out from the base of the main stem. Count the number of tillers (including main stems) from three feet of row (also at several random locations) and do the same calculation. Although there seems to be some debate about whether early nitrogen topdressing stimulates more tillers, our recommendation is that some of or all of the spring nitrogen be applied at early green-up to try to get more tillers formed if counts are low. Less than 60-70 tillers per square foot is considered low. If there are 70–90 tillers per sq. ft., it is not as critical to get nitrogen on and it can be delayed until just before the stems begin to elongate (growth stage 5). With even higher tiller counts, also delay top-dress until stage 5, as the nitrogen demand of the plant begins then. However, topdressing after stem elongation has advanced much beyond this can reduce yield.

Topdressing very early before green-up puts nitrogen out on the field before the crop can use it. With cold temperatures there probably wonâ€™t be much loss from volatilization of urea before the next rain. Ammonium forms of N are stable and won’t be lost from conversion to leachable nitrate under cold soil conditions. The main risk of loss is from nitrate forms of fertilizer applied (leaching) or under conditions where the fertilizer (in any form) is washed off the surface before it gets into the soil.

We have a video on the Crop Management Extension Group Web site about assessing wheat stands.

Spring Soil Sampling — Doug Beegle, Extension Soil Fertility Specialist

If you hadn’t collected your soil samples last fall, which is the best time to do this, it is time to start thinking about soil sampling. First, resist the urge to put off soil testing this year because of the difficult economic times we are experiencing. Soil testing is always important but even more so under current conditions. You cannot afford to have your crop come up short because of lack of nutrients after you have made a significant investment in the many inputs required to put out the crop. At the same time you cannot afford to apply extra nutrients that will not give you an economic return. The economics of soil testing are pretty simple. If you sample a 10A field every 3 years as recommended, the cost per acre is around $0.30/A/year. This very small investment in soil testing which results in recommendations that are used to manage typically $100-200 worth of nutrients on a crop that is probably worth $600–800/A. You can’t risk this magnitude of input costs and potential returns on a guess. So when times get tight we should do more soil testing, not less.

Good soil test begin with good soil samples. Here are some guidelines for getting good soil samples.

Sample uniform areas
Usually we sample each field individually. However, there may be times when we need to subdivide fields if there is the potential for significant differences across the field. Examples include: significant soil differences, part of the field receives manure but not the whole field, topographic differences such as low areas versus sidehills, etc. Also, there are situations when we can combine fields. For example when we have small strips that are all managed the same we can lump these together into one sample.
Take lots of cores
At least 15 to 20 cores should be collected to make up a composite sample to send to the lab. More is better.
Sample to uniform depth
For most routine soil testing samples should be collect to plow depth, even in no-till or permanent sods. Inconsistent sampling depth is one of the biggest sources of errors in soil sampling. This is especially true in no-till and reduced tillage systems where there is often significant stratification of nutrients in the soil.

Special note in no-till: In no-till fields an acid layer, called an acid roof, can develop right at the surface of the soil. This thin acid layer can have a significant impact on the crop but it can be missed in a normal plow depth sample. If the normal plow depth soil sample in no-till recommends liming, apply the lime as recommended and no further testing is needed. If the normal sample does not recommend lime and the field has been in long-term no-till and has not been limed recently, take a 2 in deep sample and test it for pH. This sample can be submitted to a soil testing lab or you can use a field pH test kit for this purpose. If this sample has a pH less than 6.2, then apply 1 ton of limestone even if the regular sample did not call for any limestone.
Avoid atypical areas or sample them separately
Sample between the rows and avoid any fertilizer bands as much as possible. Also, many fields have known atypical areas such as dead furrows, old fence rows, lime or manure stacking areas, wet spots, etc. If the areas are too small to manage separately, do not sample them. Taking one or two cores from these odd areas just contaminates the sample for the rest of the field. If the areas are large enough that you are able and willing to manage them separately, then take a separate sample from these areas.
Handle the sample carefully
Collect the soil cores in a clean bucket so as not to contaminate it, crumble the sample cores and air dry the sample. Mix the cores thoroughly and take a subsample to fill the mailer to send to the lab.
Fill out the soil test information sheet
Additional information such as the crop, the expected yield, the crop rotation, tillage depth, etc. are used along with the soil test results to make the recommendation. Thus, it is critical that the soil test information sheet be filled out completely and accurately.

Clover Cover Crops and Nitrogen — Douglas Beegle

With tight economic conditions there has been increased interest in using legume cover crops to supply N to corn. While this has not been the subject of a large amount of research, A recent summary of the available research has shown that red clover established in wheat or oats and then left to grow as a cover crop until the next season can contribute between 45 and 155 lb N/A to the next corn crop. In PA we have done a few experiments on this. Several years ago research in northeastern PA showed that we got 80-144 lb N/A from red clover established in wheat or oats. In more recent research in central PA, we found 62-110 lb N/A from red clover established in wheat. In a similar experiment at Landisville in 2008, the N contribution from the red clover was only 40 lb N/A. Interestingly however at this location, the corn following the clover cover crop actually required more N to achieve the maximum economic yield than the corn with no cover crop. However this was because the maximum yield following the red clover cover crop here was 30 bu/A higher than the maximum yield with no clover. Also, in 2007 at the Centre County location, the yield following the clover cover crop was 17 bu/A higher than with no cover crop. This represents a very significant non-N contribution from the cover crop which further increases the value of the cover crop. Based on this summary of research and our more limited experience in PA we can probably reliable count on 80-100 lb of fertilizer equivalent N from a good stand of red clover cover before corn. Thus for an investment of around $25/A for seed and planting, we can get around $40 worth of N, plus the non-N yield benefits from the red clover cover crop. Some farmers are also harvesting one cutting of hay from this clover which adds an additional value but the N contribution will be reduced around 30 lb/A if the hay is harvested. (See the article Wheat/Red Clover as an Alternative to Corn in Jan. 13, 2009 Field Crop News). Realize that this research reflects a significant range in the benefits and costs but it does give us some ball park figures to use in our crop planning.

Contributors: County Extension Educators: Andrew Frankenfield (Montgomery), Jeff Graybill (Lancaster), Mena Hautau (Berks), Jonathan Rotz (Cumberland). University Park: Doug Beegle, Bill Curran, Sjoerd Duiker, Dwight Lingenfelter, Greg Roth, John Tooker

Editor: John Rowehl (York)

Upcoming Events

February 17—18 Professional Crop Producers Conference

Other meetings:

February 26: No-tilling for Success grower meeting—Lebanon County Ag Center. Contact Del Voight dgv1@psu.edu
March 5, 12: Grain Marketing educational opportunities—Gratz (Dauphin Co.). For more information, contact Paul Craig phc8@psu.edu
March 11: “Winning the Game” grain marketing workshop—Lancaster Farm & Home Center. For additional information, contact Keith Dickinson, 610-696-3500, or e-mail krd16@psu.edu

Wednesday, February 10, 2010

Northeast PA No-Till Conference

Location: Harford Volunteer Fire Company, Harford, PA

Time: February 10, 2010

Details: Contact: Ryan Koch at ryan.koch@pa.usda.gov

Thursday, February 11, 2010

5th Annual North-Central PA No-Till Conference

Location: Bloomsburg, PA

Time: February 11, 2010

Details: Contact: Ryan Koch at ryan.koch@pa.usda.gov

Tuesday, February 16, 2010

Professional Crop Producers' Conference

Location: Holiday Inn, Grantville, PA

Time: February 16 and 17, 2010 (2 day event)

Details: The conference features Dwayne Beck from South Dakota on crop diversity in continuous no-tillage, Ray Archuleta with presentations on soil quality and nutrient management, and Charlie Sniffen on forages and animal nutrition. CCA CEUs will be available. Contact Sjoerd Duiker sduiker@psu.edu for more information.

Wednesday, February 17, 2010

Professional Crop Producers' Conference

Location: Holiday Inn, Grantville, PA

Time: February 16 and 17, 2010 (2 day event)

Thursday, February 25, 2010

Grazing School

Location: Berks County Agricultural Center, Leesport, PA

Time: February 25, March 4, March 11, 2010 — 7:00 pm to 9:00 pm (3 part series)

Details: Contact: Mena Hautau, +1-610-378-1327. This is a three-part series. You must attend all classes to receive credit. (4 Grazing)

Thursday, March 4, 2010

Grazing School

Location: Berks County Agricultural Center, Leesport, PA

Time: February 25, March 4, March 11, 2010 — 7:00 pm to 9:00 pm (3 part series)

Details: Contact: Mena Hautau, +1-610-378-1327. This is a three-part series. You must attend all classes to receive credit. (4 Grazing)

Thursday, March 11, 2010

Grazing School

Location: Berks County Agricultural Center, Leesport, PA

Time: February 25, March 4, March 11, 2010 — 7:00 pm to 9:00 pm (3 part series)

Details: Contact: Mena Hautau, +1-610-378-1327. This is a three-part series. You must attend all classes to receive credit. (4 Grazing)

Tuesday, March 16, 2010

Northwest Grazing Conference

Location: Dubois, PA

Time: March 16, 2010

Details: Contact Adam Dellinger at adam.dellinger@pa.usda.gov