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Agriculture and Natural Resources

The Golden Plains Area Extension Program is at the forefront on agronomic & water research. Our research spans crop production, irrigation efficiency, weed and pesticide management, crop insect control and monitoring, agricultural marketing and much more!

2022 CSU Crops Clinic

CSU Extension will be offering 14 Certified Crop Advisor credits at the upcoming 2022 Crops Clinic to be held at the Weld County CSU Extension office located in Island Grove Park, Greeley, CO. In addition, 3 core CEUs in pesticide applicator credits will be offered. The event will be held on December 8th and 9th, 2022. The Eventbrite registration has closed. If you still need to register for this program, please contact Ron Meyer at 970-349-1101 to complete the process.

Pesticides and Re-entry

          What is a restricted pesticide re-entry interval?  This interval is the restricted-entry interval (REI) into a pesticide treated area.  In other words, when is it safe to walk into a pesticide treated area.  The REI can be different for each pesticide applied and crop applied.  Some pesticides list different REI’s depending on the crop, application method, or the post-application activity (are workers hand hoeing or working on machinery in a field).  Tank mixes occur when two or more pesticides are applied at the same time.  In this case, the pesticide with the longer REI must be followed. 

          How do we find a pesticide’s REI number?  All pesticides have a “label” listed on the container.  The label is the law.  The label contains important information such as what the pesticide is (the active ingredient), what the pesticide controls (which pests), how much pesticide to apply, and the Directions for Use section.  The Directions for Use section will list the REI for the intended use.  For many common pesticides the REI is 24 hours while some applications require 48 hours.  The REI is different for each pesticide, application and crop.  Always find a pesticide’s REI before entering into a treated area.  After a pesticide application’s REI has expired, the area is considered safe for re-entry.  REI’s for some of the typical pesticides used are 2,4-D 48 hours, Glyphosate 12 hours, Sevin garden insecticide 12 hours. 


Pesticide Label for Chlorpyrifos Cancelled

     The Environmental Protections Agency (Agency) has cancelled all food tolerances for the insecticide Chlorpyrifos as of February 28, 2022.  As a result, Chlorpyrifos is no longer labeled for insect control in any food crop.  Food crops are identified as corn, wheat, sunflower and other grains, vegetables, and fruits.  Field crops treated with Chlorpyrifos will not be eligible to sell into food or feed markets.  The change is a result of health links to neurodevelopmental effects.   Chlorpyrifos is an organophosphate insecticide, acaricide and miticide used primarily to control foliage and soil-borne insect pests and is common locally under the name Lorsban.

     Since its first registration in 1965, chlorpyrifos has been reviewed several times by EPA for tolerance reassessment, reregistration, and most recently, as part of its ongoing registration review. While in the 2020 revised human health risk assessment the Agency determined that risks from exposures to chlorpyrifos residues in food were not of concern but drinking water exposures significantly added to those risks. When considering the drinking water contribution from all currently registered uses, the Agency’s levels of concern are exceeded when combined with food and residential exposures.  Therefore, the Agency decided to cancel all food uses of Chlorpyrifos.

     Remaining Chlorpyrifos cannot be applied to any site that is not on the label.  Contact your local pesticide dealer for information regarding returning leftover product.  Non-food crop uses are still allowed such as some ornamental applications.

Source: EPA, Cropwatch: UNL


Environmental conditions affect plant growth in many ways.  Conditions that are too dry or too wet, too cold or too hot can all affect wheat production and survival.  Determining whether wheat plants are alive in the spring due to adverse growing conditions should be done before spending production dollars on those acres.

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Tillage with No-Till?

Almost 3 million acres of Colorado farmland employs no-till strategies, and this acreage is expected to continue to increase. No-till farming has continued to gain momentum in the state due to a number of positive factors associated with this technique. Benefits of no-till include decreased soil erosion, increase soil moisture retention, decrease in fuel ussage associated with tillage, decreased labor costs from not tilling, increased soil carbon, and increased soil organic matter. Most of these benefits result in increases to farm income. However, crop production issues with no-till are showing up more frequently. Issues include herbicide resistant weeds (herbicides for weed control are substituted for tillage) and soil compaction problems.

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Wheat Stem Sawfly

Wheat stem sawfly is a native insect that feeds on grasses in Colorado. The insect was first identified by entomologists in Colorado around the late 1800’s and primarily fed on range grasses. However, wheat stem sawfly emerged as a Colorado wheat pest in 2010 and damage from this insect has been expanding and increasing since. Today, this pest is estimated to cause $30 million in damage, according to Brad Erker, Executive Director of the Colorado Wheat Research Foundation. As a result, Colorado State University (CSU) is focused on addressing cropping strategies to ease pest losses to this insect. Research is focused on cropping rotations and developing wheat varieties that discourage wheat stem sawfly from reproducing and damaging plants.

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Got Rye in Your Wheat

Feral rye, along with other annual grasses, are troublesome pests for wheat producers. Rye, along with jointed goatgrass and cheat grass, cost Colorado Wheat producers’ money annually in terms of reduced yield and increased dockage. However, a newer wheat production system termed CoAXium Wheat Production System is an option for wheat producers who have annual grassy weeds. The CoAXium wheat Production System is a herbicide tolerance technology based on a non-gmo AXigen wheat trait. The technology was developed at Colorado State University and is owned by the Colorado Wheat Research Foundation. CoAXium is the name for the production system, Axigen is the wheat gene, and Aggressor is the herbicide. Aggressor applied to CoAXium wheat varieties provides control of winter annual grasses such as feral rye, downy brome (cheat), and jointed goatgrass.

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Can food production occur in concert with solar power generation?  Recent advancements and  interest in solar generated power has some asking “will large solar panel projects decrease available land for crop production?” Continue reading HERE

Colorado Department of Agriculture

Pesticide Applicator Certification and Licensing Program

The Certification & Licensing program promotes the safe and effective use of pesticides and certain devices to control pests such as insects, rodents, and weeds which may harm crops, livestock, beneficial organisms, structures and individuals through the certification of commercial and private pesticide applicators. The program protects the public and environment from the potentially adverse effects of pesticides that may result from unsafe and incorrect pesticide use.

Click here to find more information at CDA Plant Division

Certified Crop Advisors (CCA)

Contact:  Kierra Jewell, CCA Representative

Each season a new group of professionals who voluntarily chose to enhance their skills and knowledge in the field of Agronomy qualify for becoming Certified Crop Advisors.  CCA’s pass two comprehensive exams covering nutrient management, soil and water management, integrated pest management, and crop management.  Along with contributing to the agronomic community and gaining the required experience, they commit to focus on grower profitability while optimizing and protecting our natural resources.

The International Certified Crop Adviser (ICCA) Program is the largest voluntary, agriculturally oriented certification program in North America.  Over 13,000 agronomy professionals have met the standards-exams, experience, education, ethics-set by the American Society of Agronomy (ASA) to become certified.

If you have any questions about the CCA Program or would like to find a local CCA, please visit or contact Kierra at (970)491-6201.

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