I went on a farm call last week (early May) in response to a suspected herbicide injury issue in a recently replanted almond orchard.  The grower had applied a tankmix of glyphosate and Goal as a preplant burndown treatment a week or so before planting.  In some areas of the field, the first leaves were badly stunted and yellowed and the grower and PCA wondered if was caused by the preplant treatment.



Although the symptoms are pretty classic for glyphosate exposure (stunted leaves, shortened internodes or "witches brooming", and chlorosis of the newest growth), this injury didn't make sense with the herbicide application in this field.  There was not an obvious pattern of injury spatially across the field;...

I only have a moment to post today but wanted to put up two links concerning the research and publications of a retired Purdue University researcher.  Dr. Don Huber has made a number of claims about the effects of glyphosate-resistant cropping systems on soil pathogen populations and micronutrient uptake.  I have received several calls about this (particularly the micronutrient aspect) in recent months.

The first link is to a Washington Post article entitled "Researcher's warning about genetically modified crops spreads, but scientists question...

Today I wanted to follow up on my post from a few weeks ago about volatile organic compounds (VOC) from herbicides and other non-fumigant pesticides. In case you missed it, the discussion on February 27 was about an online VOC calculator developed by California Department of Pesticide Regulation (CDPR). This tool allows users to compare calculated VOC emissions of individual pesticides or season-long pesticide programs.

A quick post today on a recent report of resistance to glufosinate, the active ingredient in Rely herbicide (also sold as Liberty, Ignite, Basta, etc in other markets).

Researchers in Malaysia reported a few years ago on a population of goosegrass resistant to glufosinate in vegetable and orchard systems (Lee L J & Ngim J (2000). A first report of glyphosate-resistant goosegrass (Eleusine indica (L) Gaertn) in Malaysia. Pest Management Science, 56, 336-339).  For a number of years this was the only reported case of resistance to this herbicide.

At a meeting last month, I saw a presentation by Wilson Avila and Carol Mallory-Smith from Oregon...

Earlier this month, I attended the 2011 Plant and Soil Conference which was held in Fresno this year.  This annual meeting put on by the California Chapter of the American Society of Agronomy (http://calasa.ucdavis.edu/ ) usually has several sessions during the two-day program designed to update Certified Crop Advisors, Pest Control Advisors, and other professional agronomists on current research and regulatory issues.  One of the speakers in the Environmental Quality Session, Pam Wofford from CDPR, spoke about reducing emissions of Volatile Organic Compounds (VOC) from pesticides by switching formulations.  I thought I’d touch on that issue today.

There are a number of definitions of...