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Resources by Doug Horn

Title Available As Summary Date ID Author
Spray Water Quality and Pesticide Characteristics
Pesticide sprays consist of at least 95% water. Water quality plays an important role in pesticide performance. The following issues may indicate a compatibility problem with pesticides and spray water quality: - Pesticide does not work at labeled rates; - Difficulty mixing sprays or clogging of nozzles; - Inconsistent pest control observed in fields or plots; - Pests seem resistant to a new pesticide active ingredient, or - Crops are lower quality or lower yielding. Understanding how water quality characteristics such as pH, water hardness, turbidity, and total suspended solids affect the adsorption and persistence (half-life, storage time) of a pesticide can help pesticide applicators reduce or eliminate compatibility issues and improve pesticide effectiveness
Feb 22, 2024 BSE-350P
Understanding Spray Tank Mixing Practices
Mixing two or more pesticide products can allow for the treatment of several pests at the same time, improve pesticide performance, and ultimately saving time and money. However, physical and chemical tank mix incompatibilities can occur when combining two or more pesticides. Physical incompatibility is the failure of pesticide products to stay uniformly mixed and can result in layering, products settling out of solution, or clumping. A chemical incompatibility is the result of a chemical reaction between pesticide products. A chemical incompatibility is less visible and can be harder to detect. This publication focuses on basic factors that influence product compatibility (agitation speed and method, water temperature, mixing order, carrier type, and chemical formulations) and summarizes best mixing practices to address these factors.
Feb 22, 2024 BSE-351P
Solving Spray Water Problems
Spray water problems may arise due to water quality and management decisions. Certain aspects of water quality can reduce the efficacy of the pesticide as well as affect how the pesticide interacts with the plant surface or targets pests. Evaluating and testing spray water chemistry can help identify water quality problems that might otherwise be overlooked. This publication will examine possible solutions to spray water problems, including the use of adjuvants and other additives to enhance pesticide performance.
Feb 15, 2024 BSE-352P
Herbicides for Growth Suppression Along a Temporary Fence
Strip grazing summer stockpiled fields allows maximum utilization of the forage. Temporary fencing must be installed through taller residue, much of which is tall fescue seed heads. Several products were identified which effectively reduced the number of tall fescue seed heads.
Nov 24, 2020 SPES-269-3
Drill Calibration Worksheet Jan 14, 2021 SPES-283NP
Virginia Corn Silage Hybrid Trials in 2021 Dec 16, 2021 SPES-364NP
Virginia Corn Hybrid and Management Trials in 2021 Dec 17, 2021 SPES-365NP
VCE Ag Today: Understanding Spray Water Chemistry May 7, 2021 VCE-1027-48NP
Augusta County 2023 Situation Analysis Report
Virginia Cooperative Extension takes pride in the premise that vital programming is based on the issues, problems, and needs of the people. A thorough analysis of the situation provides context for understanding and addressing these problems. Each local office updates their situation analysis every 4-5 years.
Feb 29, 2024 VCE-596-9NP (VCE-1175-9NP)