New restricted use insecticide registered for aphids on soybean

Contributed by Mike Helms, Pesticide Management Education Program

The New York State Department of Environmental Conservation (NYSDEC) recently approved the registration of three insecticides containing the active ingredient afidopyrofen. These are the first products registered in New York State containing this active ingredient. Products registered include:

  • Sefina Inscalis Insecticide (EPA Reg. No. 7969-391) – registered for use on several agricultural crops including cucurbits, fruiting vegetables, tuberous and corm vegetables and soybean against various aphids and whiteflies.
  • Versys Inscalis Insecticide (EPA Reg. No. 7969-389) – registered for use on brassicas, leaf petiole and leafy vegetables, pome fruit, and stone fruit against various aphids and whiteflies.
  • Ventigra Insecticide (EPA Reg. No. 7969-393) – registered for use on ornamentals and vegetable transplants against aphids, whiteflies, mealybugs, and scale.

Note that all three of these products are restricted-use in New York State and their use in Nassau and Suffolk Counties are prohibited. The labels for these products also have NY-specific buffer zone requirements.

Copies of the approved labels for these products are available from the NYSDEC’s product registration website.

Questions should be directed to Cornell PMEP.

Print Friendly, PDF & Email

Hemp Added to NNY Field Crops Health Survey; NNYADP Posts Results

Growers at a field crops meeting on a past August day in Northern New York. Photo: NNYADP

Industrial hemp and alfalfa have been added to the annual crop health survey funded by the farmer-driven Northern New York Agricultural Development Program (NNYADP). Cornell Cooperative Extension (CCE) field crops specialists scouted fields on 30 regional farms in 2019 for early detection of disease in corn, soybean, alfalfa, and hemp crops. The results of crop surveys from 2013 through 2019 are posted on the NNYADP website at www.nnyagdev.org.

“This regional survey is a proactive and systematic way to alert growers to respond quickly to limit emerging and re-emerging plant diseases, to document trends, and to develop strategies to maintain crop health, sustainability, and the profit margin that is so narrow for growers,” says project leader and CCE Regional Field Crops Specialist Michael E. Hunter.

This NNYADP field crops survey, restarted in 2013, has traditionally focused on corn and soybean as foundational crops, grown as both livestock feed and cash crops, for the regional farming industry. Hunter says, “Alfalfa has been added to the survey as another essential dairy industry crop, and, with grower interest increasing in industrial hemp, we began scouting those plantings in 2019.”

Hunter and CCE Regional Field Crops and Soils Specialist Kitty O’Neil scout fields and send samples of plant tissue for diagnosis at the Bergstrom Pathology Lab at Cornell University in Ithaca, N.Y.

In 2019, the NNYADP crop health survey identified 13 crop diseases: 2 in corn, 7 in soybean, 2 in alfalfa, and 2 in industrial hemp.

Northern stem canker was identified in soybean but was not problematic in NNY in 2019. Hunter notes, “While there have been significant yield losses reported to this disease in Midwestern states, to date, no yield loss has yet been documented in New York State crops to northern stem canker.”|

Warm, wet weather conditions during podfill in 2019 fostered development of Cercospora leaf blight,  non-yield limiting disease in soybean. Levels did not result in any rejection of loads shipped to market. Other soybean diseases identified in NNY in 2019 were downy mildew, white mold, frogeye leaf spot, anthracnose, and Septoria brown spot.

The cool, wet spring of 2019 favored growth of Leptosphaerulina leaf spot and Stemphylium leaf spot in alfalfa crops; however, incidences were not severe nor widespread, and neither disease negatively impacted forage quality or overall crop yield.

White mold and Botrytis gray mold, common molds that can cause serious damage in industrial hemp grown in the field and in greenhouses, were seen in plantings of industrial hemp, an emerging crop in Northern New York.

FIrst-time confirmations of emerging diseases are added to state and national crop pathogen databases with field samples archived in the Cornell University Field Crop Pathogen Culture Collection. DNA sequences of any confirmed new pathogens are submitted to the National Institutes of Health Gen Bank genetic sequence database.

“This yearly scouting and diagnosis survey project adds data, distribution mapping, and trending to help growers adapt their strategies for maintaining crop health, preventing disease, and efficiently and cost-effectively treating issues locally, regionally, and statewide,” Hunter adds.

Funding for the Northern New York Agricultural Development Program is supported by the New York State Legislature and administered by the New York State Department of Agriculture and Markets.

Print Friendly, PDF & Email

PESTICIDE CERTIFICATION DURING PAUSE-NY

Mike Hunter, Regional Field Crop Specialist, North Country Regional Ag Team

I wanted to take this opportunity to share with you timely information regarding the sale of restricted use pesticides to applicators that failed to obtain sufficient continuing education credits necessary for recertification of their NYS pesticide applicator license.

On April 7, 2020 the NYS DEC issued an Enforcement Discretion for Extension of Pesticide Applicator Recertification and Business and Agency Registration during the COVID -19 Emergency notice (found here: https://www.dec.ny.gov/chemical/298.html).

Here are the highlights of this action and how it applies to pesticide applicators with expired licenses:

    • Any applicator, both private and commercial, whose certification lapsed on or after November 1, 2019 is allowed to possess, purchase and apply restricted use pesticides until 60 days from the expiration of Executive Order 202 (issued March 7, 2020 and found here: https://www.governor.ny.gov/news/no-202-declaring-disaster-emergency-state-new-york)
    • As of now, the Executive Order 202 expires September 7, 2020. The enforcement discretion will expire 60 days from that date or any extensions issued to it.
    • The pesticide applicator must follow these steps during the period of time outlined:
      • Make sure that their applicator card expiration date is after November 1, 2019
      • Keep the expired applicator card in their possession
      • Have a printed copy of the Enforcement Discretion Letter in their possession
      • Present both the expired license and a copy of the Enforcement Discretion letter to the pesticide dealer when purchasing restricted use pesticides.

It is strongly recommended that the pesticide business that sells restricted use pesticides to a person with an expired applicator license retains a copy of both the expired license and the enforcement discretion letter on file.  This will provide added insurance in case there is any question that may arise in the future.  Again, make certain the person’s license expired after November 1, 2019 prior to making the sale.  This special arrangement DOES NOT apply to applicators whose licenses expired before November 1, 2019.  If a person does not have a copy of the Enforcement Discretion Letter please print a copy for them to carry and one for you to keep on file.

If you have any additional questions regarding this matter please contact your local NYS DEC pesticide control specialist in your region of the state.  The NYS DEC statewide directory can be accessed here: https://www.dec.ny.gov/about/558.html

Print Friendly, PDF & Email

Report Seedcorn Maggot and Wireworm Damage: WE NEED YOUR INPUT

Given the recent controversy surrounding the proposed legislative bans on some pesticides in NY, Cornell researchers and extension specialists are working to provide necessary data on the efficacy, usefulness and perceived need for these products in our agricultural systems.  To do this, we need your help with identifying, documenting and quantifying losses to early season pests, such as seedcorn maggot and wireworm in your corn and soybean fields.

pest in soybeanA collaborative effort between the NYS Integrated Pest Management program and Cornell Cooperative Extension field crop specialists will begin in 2020 with the goal of monitoring for and documenting losses to pests that the neonic seed treatments are intended to protect against.  Given the sporadic distribution of damage caused by seedcorn maggot and wireworm, it can be challenging to quantify losses to these pests in research plots alone.  Therefore, we need assistance from farmers, crop consultants, agribusiness associates, and crop insurance claim adjusters to report fields with damage from these pests across NY State.

Your valuable input would require nothing more than a phone call or email to your local field crops extension specialist to report the specific location of damage soon after planting, while pests are still active and can be confirmed (by V2 stage).  The extension specialist will then visit the field to confirm pest activity, and may conduct plant stand counts to estimate potential yield losses.  Location and farm identity will remain anonymous, as we are only interested in quantifying losses across NYS, not where they occur.

Claims on the value (or lack thereof) of these insecticide seed treatments in NY field crop production cannot be validated or quantified without this sort of data, and we can’t obtain this statewide data without your assistance.  Therefore, whether you grow corn for silage or grain (or even sweet corn), soybean or dry beans, conventionally or organically, we need to hear from you!  Please refer to the following list of specialists to contact in your region to report damage from seedcorn maggot or wireworm in your fields this spring:

Mike Stanyard (NWNY CCE) – mjs88@cornell.edu, 585-764-8452

Jodi Putman (NWNY CCE) – jll347@cornell.edu, 585-991-5437

Jaime Cummings (statewide, NYS IPM) – jc2246@cornell.edu, 607-255-1747

Josh Putman (SWNY CCE) – jap473@cornell.edu, 716-490-5572

Janice Degni (SCNY CCE) – jgd3@cornell.edu, 607-391-2660, x414

Ron Kuck (Cayuga Co. CCE) – rak76@cornell.edu, 315-255-1183, x242

Jeff Miller (Oneida Co. CCE) – jjm14@cornell.edu, 315-736-3394, x120

Kevin Ganoe (CNY CCE) – khg2@cornell.edu, 315-866-7920, x230

Aaron Gabriel (ENY CCE) – adg12@cornell.edu, 518-380-1496

Ken Wise (ENY, NYS IPM) – klw24@cornell.edu, 845-677-8223

Christian Malsatzki (SENY CCE) – cpm78@cornell.edu, 845-340-3990

Joe Lawrence (statewide, PRO Dairy) – jrl65@cornell.edu, 315-778-4814

Mike Hunter (NNY CCE) – meh27@cornell.edu, 315-788-8450, x266

Kitty O’Neil (NNY CCE) – kao32@cornell.edu, 315-854-1218

Elson Shields (Cornell Field Crops Entomologist) – es28@cornell.edu, 607-255-8428

Print Friendly, PDF & Email

2020 Cornell Guide for Integrated Field Crop Management Now Available

2020 Field Crops Guide CoverThe Pesticide Management Education Program (PMEP) at Cornell University is pleased to announce the availability of the 2020 Cornell Guide for Integrated Field Crop Management.

Written by Cornell University specialists, this publication is designed to offer producers, seed and chemical dealers, and crop consultants practical information on growing and managing field corn, forages, small grains, and soybeans. Topics covered include nutrient management, soil health, variety selection, and common field crop pest concerns. A preview of the Field Crops Guide can be seen online at https://cropandpestguides.cce.cornell.edu.

Highlighted changes in the 2020 Cornell Field Crops Guide include:

    • Revised pesticide options for economically important field crop pests.
    • Updated corn, forage, and small grain variety trial and research data.
    • Pesticides available for stored grain management.

Cornell Crop and Pest Management Guidelines are available as a print copy, online-only access, or a package combining print and online access. The print edition of the 2020 Field Crops Guide costs $31 plus shipping. Online-only access is $31. A combination of print and online access costs $43.50 plus shipping costs for the printed book.

Cornell Guidelines can be obtained through your local Cornell Cooperative Extension office or from the Cornell Store at Cornell University. To order from the Cornell Store, call (844) 688-7620 or order online at https://www.cornellstore.com/books/cornell-cooperative-ext-pmep-guidelines.

Print Friendly, PDF & Email

Pricing Corn Silage — Fall 2019

John J. Hanchar, Cornell University/College of Agriculture & Life Sciences, <jjh6@cornell.edu>

Summary

    • Analysis suggests corn silage price depends on corn silage quantities, alfalfa hay price, the price received by farmers for milk, and corn grain price.
    • Analysis for NY suggests that estimated corn silage price is most sensitive to corn silage quantities, alfalfa hay price and corn grain price.
    • Price estimates combined with understanding of relevant supply and demand factors from an individual farm business owner’s perspective can aid decision making regarding corn silage price. Given recently available alfalfa hay and corn grain prices (May through July, 2019, and August 27, 2019, respectively), price analysis for NY suggests an estimated corn silage price of about $45 per ton.  The Fall 2018 estimate was about $41 per ton.

Determining Corn Silage Price

A farm business owner can examine how much corn silage he/she would be willing to supply to a market at a given price.  Analysis of the farm business’ cost structure for corn silage production combined with consideration of other factors help to define the supply relationship.  A seller can develop a target based upon the above, but actual market conditions provide no guarantee that a buyer will purchase quantities desired at a price that achieves the producer’s target.

Some farm business owners might approach the problem of determining corn silage price from a value in production, or input demand perspective.  Amounts of corn grain and corn stover in a ton of corn silage, relevant prices, and corn silage’s place in the milk production process are key factors.  A buyer can develop a price target based upon the above, but actual market conditions provide no guarantee that a producer will sell the quantity desired at a price that matches the buyer’s willingness to pay target.

Although factors in price determination, the two approaches described above in isolation, don’t completely determine price and quantity.  Supply and demand relationships work simultaneously in markets to determine price and quantity.  Empirical price analysis brings supply and demand relationships together to determine price.

Corn Silage Price Analysis

Empirical price analysis suggests that corn silage price is a function of corn silage quantities, alfalfa hay price, the price received by farmers for milk sold, and corn grain price.  The ordinary least squares regression model here expresses corn silage price as a linear function of the above variables.  The statistical analysis used here is fairly basic.  However, readers of the original August 2012 Ag Focus article describing this work, and readers of annual update articles note that the analysis and estimates help farm business owners price corn silage.

Corn Silage Price Estimates – Fall 2019

The ordinary least squares regression model reported in August 2012, updated here to reflect additional data available to date and changes in other underlying factors, produced corn silage price estimates for NY.  Below, estimated corn silage price is a function of alfalfa hay price and corn grain price with other factors (corn silage production and milk price) fixed at expected levels.  Expected corn silage quantity is set at 8,365 tons, the average for the period 2007 through 2017.

    • estimated corn silage price ($/ton) = -3.1431 + (0.1845 x price of alfalfa hay ($/ton)) + (3.5138 x price of corn for grain ($/bushel))

Suppose

    • NY alfalfa hay price is $186 per ton, the three month average of the period May, June, July 2019. (USDA/NASS.  Agricultural Prices. Washington, DC:  National Agricultural Statistics Service.  July 31 and August 30, 2019 releases), and
    • corn grain price is $3.94 per bushel (Western NY Energy.  “Corn Bids.” August 27, 2019.  Approximate value based upon reported bids for fall 2019.)

Using the estimating equation and the above prices for alfalfa hay and corn grain as expected prices, estimated corn silage price is about $45 per ton.  Compare this to last fall’s estimate of about $41 per ton.  Suppose alfalfa hay price is $179 per ton, the annual average for the period 2007 through 2017, and expected corn grain price is 3.94 dollars per bushel, then estimated corn silage price would be about $44 per ton.  Buyers and sellers use an estimate as a base, typically, adjusting for quality and, or costs for harvest, hauling and storage based upon the situation, for example, when pricing standing corn for silage.

Corn silage price estimates combined with understanding of relevant supply and demand factors from the individual farm business owner’s perspective, including local conditions, for example, growing conditions, can aid decision making regarding corn silage price.

Print Friendly, PDF & Email

USDA to Measure Small Grain Production

During the week of August 26th, growers of small grains around the country will receive survey forms from the U.S. Department of Agriculture’s National Agricultural Statistics Service (NASS). The agency is taking a comprehensive look into the 2019 production and supply of small grains, which include wheat, oats, barley, and rye.

“The small grains industry is an important part of Northeastern agriculture and it is crucial for all involved with the agriculture sector to have accurate data about this key sector of the economy,” explained King Whetstone, director of the National Agricultural Statistics Service. “We will contact more than 4,000 producers in Delaware, Maine, Maryland, New Jersey, New York and Pennsylvania to accurately measure 2019 acreage, yield, and production for small grain crops. The data collected from this survey will also help set small grain acreage, yield, and production estimates at the county level, to be published in December 2019.”

NASS will contact survey participants to gather information on their 2019 production and the quantities of whole grains and oilseeds stored on farm. As an alternative to mailing the survey back, and to help save both time and money, growers will have the option to securely respond to the survey online. Farmers who have not responded by August 30, 2019 may receive a phone call or visit from a NASS representative who will help them fill out the survey form.

“NASS safeguards the privacy of all respondents and publishes only county, State and National level data, ensuring that no individual operation or producer can be identified,” stated Whetstone. “We recognize that this is a hectic time for farmers and ranchers, but the information they provide helps U.S. agriculture remain viable and capable. I urge them to respond to these surveys and thank them for their time and cooperation,” said King Whetstone.

NASS will analyze the survey information and publish the results in a series of USDA reports, including the annual Small Grains Summary and quarterly Grain Stocks reports, both to be released September 30, 2019. Survey data also contribute to NASS’s monthly and annual Crop Production reports, and the USDA’s World Agricultural Outlook Board’s monthly World Agricultural Supply and Demand Estimates (WASDE).

All NASS reports are available online at https://www.nass.usda.gov/Publications/. For more information call the NASS Northeastern Regional Office at (800) 498-1518.

Print Friendly, PDF & Email

Incentive Program Survey – make your voice heard!

Cover crop, Diakon radish field and blue sky

Cornell University, with support from Sustainable, Agriculture, Research, and Education (SARE), is conducting a survey for all fruit, vegetable, field crop, grain, and mixed crop-livestock producers in New York, Pennsylvania, Maryland, and Vermont to identify the biggest challenges that farmers face, as well as the best solutions in regards to cover crop incentive programs. You do not need to have experience with cover crops to participate.

Our goal is to understand what the most important factors are for farm owners and managers when deciding whether or not to use incentive programs. Notably, the survey also provides an opportunity to share your experience managing issues related to cover crops and incentive program requirements.

Key findings from the survey will be published and communicated to grower organizations and other farmer advocates so that recommendations, actions, and outcomes reflect what you identify as being most helpful for your operation. Whether your farm is small or large, organic or conventional – your responses to this survey can be a powerful tool for change.

Please click the below link fill out the survey:
https://cornell.qualtrics.com/jfe/form/SV_41vvNzqOIAQTmyF

Print Friendly, PDF & Email

Immature and Variable Maturity Corn Silage for 2019

Kitty O’Neil, Ph.D, Field Crops & Soils Specialist and Team Leader – North Country Regional Ag Team, Cornell University Cooperative Extension

This has been a challenging year to grow corn in the North Country.  Extremely wet weather delayed or prevented field fitting and corn planting, and saturated soil conditions limited plant development in June and early July.  Despite this poor start, some corn fields look remarkably good, almost normal.  But most fields are weeks behind and may be sporting some version of the ‘rollercoaster’ look – with bare spots, replanted areas and plants of variable height and maturity.  Some fields, or parts of fields, will probably not reach full maturity while the best parts may.  Some corn plants will have normal ears; some plants may have unusually small ears or poor grain fill, or even no ears at all, at harvest time. Dr. Bill Cox at Cornell determined that corn requires 750 to 800 GDD86/50 from silking, to reach 32% moisture, nearly harvesting stage.  This variable maturity will present some problems when chopping silage in a few weeks.  Dr. Larry Chase from Cornell University has outlined some key points to keep in mind during corn silage harvest in this sort of year.  He makes 4 main points.

Late planted and thin corn field in St. Lawrence County, July 1, 2019.
Late planted and thin corn field in St. Lawrence County, July 1, 2019. Photo by K. O’Neil.

Yield will be highly variable and difficult to estimate. Dr. Greg Roth at Penn State suggests that silage yield for corn without ears or with poorly pollinated ears may be 1 ton of wet silage yield (30% DM) per foot of plant height. An older study at Cornell by Dr. Bill Cox indicates that silage yields at the dough stage are 65 to 70% of yields at the milk line stage.  In the same study, yields at the silk stage were 40 to 45% of those obtained at the milk line stage.

Some growers like to estimate yield and quality of standing corn so that it may be sold for silage before harvest.  Estimating yield of highly variable fields is risky.  It’s possible to weigh DM from sampled row lengths and calculate yield of the whole field, but the number of samples required for an accurate estimate in these variable fields is prohibitively high.  Instead, as fields are chopped, silage wagons or trucks should be counted and a representative sample of them should be weighed to calculate a more accurate yield and price.

Harvest management requires some additional planning and checking.  When the most mature plants in a corn field are at the proper dry matter (DM) content for harvest (32-24% DM), the less mature plants will be much wetter (less than 30%).  For fields with variable maturity, wait until the average whole plant DM for the field is 32-34% DM.  Harvesting wetter forage will increase runoff losses from the silage and make it difficult to get a good fermentation.  If possible, store immature corn silage separately from proper maturity silage.

Check chopper settings and particle size of the material coming out of the chopper. If using the Penn State box, target 10-20% on the top screen and < 40% in the pan. This may require increasing length of cut.  Since ear and kernel development on under-developed corn is poor, kernel processing may not be needed.  Follow normal silage management practices of filling fast, packing and covering the top with plastic or with oxygen limiting barriers.  Immature corn silage is generally high in readily available carbohydrates to support good fermentation, however, it may be low in the natural bacterial population entering the silo on the corn plant. The addition of a lactic acid-based inoculant may be beneficial to stimulate fermentation in this case.  Lastly, give the silo 3-4 months of fermentation before feeding out.

Estimating value for corn silage when it is so variable – is tough.  The sale price of variable maturity or immature corn silage will depend on yield, dry matter content and nutrient composition. Dr. Bill Weiss at Ohio State indicates that immature corn silage is worth about 85% of the economic value of normal corn silage – if it is the same dry matter content.  Dr. Larry Chase provides examples of price calculations that consider the Ohio State conversion and variable DM content.

If the value of “normal’ corn silage = $70/ton (assuming 35% DM), then the value of immature corn silage = $70 * 0.85 = $59.50 (still assumes 35% DM). If the actual dry matter of the immature corn silage is only 27%, then the adjusted price = 27/35 *$59.50 = $45.90/ton.  To ballpark the value of the standing crop, use 70% of the adjusted price. This would be $41.65 for this example of immature corn silage at 27% DM standing in the field.

Penn State researchers have developed a more detailed spreadsheet for pricing standing corn for corn silage based on the value of grain corn.

When using any of these methods for valuing corn for corn silage in 2019, consider that estimating yield of the standing crop may be the most uncertain component in your calculations.  Therefore it may be best to count and weigh trucks or wagons rather than estimate yield.

Nutritional value of this immature and variable crop will present another challenge. In addition to variable moisture content, nutrient composition of the corn silage will also vary with maturity, so periodically collect samples of the chopped forage during harvest to provide information on the nutrient content of the silage for use in ration balancing.  Less mature corn is likely to be higher in crude protein, higher in fiber, higher in sugar and lower in starch than normal corn silage.  Because the fiber in immature corn is more digestible, the energy value of immature silage may be 85-95% of normal, despite the significantly lower starch content.  A wet chemistry analysis may be more accurate than NIR analysis since NIR calibrations for normal corn silage may not accurately predict immature silage composition.

Work with your nutritionist to determine the best use for your variable maturity or immature corn silage.  You may decide to feed immature corn silage only to specific groups of cows or young stock depending on its nutrient composition. Immature corn silage can have higher acetic acid content after fermentation which can decrease dry matter intake if not neutralized. The addition of sodium bicarbonate added to the ration at 0.75% of total ration dry matter may help.

Additional resources:

    1. Working with Immature Corn Silage. August 2013. L. E. Chase, Cornell University.  http://www.ccenny.com/wp-content/uploads/2013/02/Considerations-for-Working-with-Immature-Corn-Silage-2013.pdf.
    2. Pricing Standing Corn Spreadsheet. Beck et al.  Penn State Cooperative Extension.  http://www.ccenny.com/index.php/2013/08/22/pricing-standing-corn-for-silage-spreadsheet/

For more information about field crop and soil management, contact your local Cornell Cooperative Extension office or your CCE Regional Field Crops and Soils Specialists, Mike Hunter and Kitty O’Neil.

Kitty O’Neil Mike Hunter
CCE Canton Office CCE Watertown
(315) 854-1218 (315) 788-8450
kitty.oneil@cornell.edu meh27@cornell.edu

Print Friendly, PDF & Email

The Muddy Boot Weed Seed Dispersal Method

Josh Putman, Field Crops Specialist, CCE SWNY Dairy, Livestock, and Field Crops Team

Tall waterhemp is one of the most problematic weed species throughout the Midwest and has now arrived and spread to eight counties in Upstate New York. Waterhemp can spread from field-to-field and farm-to-farm on equipment, clothing, application equipment, or via water from over flooded ditches and rivers. Following a recent field day event we wanted to demonstrate the amount of weed seed that could travel back with you.

Boots that were considered “clean” were not as clean as we had thought (Figure 1). A knife was used to clean the boots and break up any hard clots that were present. Once the boots were clean, tweezers were used to separate the weed seeds from the dirt (Figure 2). The pigweed/waterhemp seed was then separated from other weed seeds that were present, and pigweed seeds were counted (Figure 3). The clods of dirt were also checked, and one pigweed seed was found stuck to a clay particle (Figure 4).

Figure 1: Muddy boots
Figure 1: Muddy boots – Photo: Josh Putman
Figure 2: Tweezers used to separate weed seed from dirt
Figure 2: Tweezers used to separate weed seed from dirt – Photo: Josh Putman
Figure 3: Seeds were separated and counted; 17 total pigweed seeds
Figure 3: Seeds were separated and counted; 17 total pigweed seeds – Photo: Josh Putman
Figure 4: One pigweed seed hidden in a clay particle
Figure 4: One pigweed seed hidden in a clay particle – Photo: Josh Putman

An estimate of a 3 year establishment of waterhemp assuming 50% of the seeds were waterhemp and 100% were waterhemp was then calculated, respectively. The calculations are seen below:

16 pigweed seeds + 1 pigweed seed hiding in soil = 17 pigweed seeds from 2 boots.

Assuming only half of those are waterhemp and it can produce 250,000 seeds per female plant: 17/2 = 8.5 X 250,000 = 2.125 million seeds the following year in a field.

Assuming every seed on the bottom of the boots are waterhemp: 17 X 250,000 = 4.250 million seeds the following year.

Assuming 75% survival rate and reproduction in year 2: 4.250 million X 75% = 3.1875 million plants X 250,000 seeds per plant = |

**796,875,000,000 seeds going into the soil in year 3 (potentially)

In conclusion, correct and early identification is very important; learn the correct characteristics of the plants (Figure 5) and seeds. Proper cleaning and sanitation of equipment, clothing, and vehicles can help prevent spreading. Intense management and continuous scouting are vital to eradication of this weed species. Mechanical control such as plowing can bury the seed deep which might decrease seed bank numbers. And, if in doubt, contact your local CCE specialist for help with identification or other management practices.

Figure 5: Tall Waterhemp (left) vs. Smooth Pigweed
Figure 5: Tall Waterhemp (left) vs. Smooth Pigweed

 

Print Friendly, PDF & Email