A few months ago I wrote about starting some tests looking at various postemergence herbicides for non-crop use. This project was initiated due to new ordinances some cities in southern California were considering or adopted that limited the use products containing glyphosate on city owned property. I changed up some of the products from the original test I did and repeated some others.
Some are listed as organic and some are organic but not be organically approved by a certifying agency e.g. OMRI. One is listed as a biopesticide (Fiesta). One is a synthetic pesticide (Finale) that may be a good replacement in certain situations.
- Author: Cheryl A. Wilen
There has been more than the usual number of questions about what I am calling "bio-based" herbicides recently. Arguably, this is coming from news that some school districts and cities specifically calling out the use of glyphosate on the properties they manage. Landscaping departments want to know which of the products available work the best.
To start, please be aware that all of these products are contact herbicides that will not move through the plant. Therefore, they will not be effective if you are trying to get to any underground organ such as the roots, rhizomes, tubers, etc. of any perennial plant. Do not try to make a head to head comparison...
When Richard Smith tells you that he is impressed with efficacy of an organic herbicide you better take notice. Richard shared his results on this blog site last year and showed good weed control with 'Suppress' from Westbridge. This OMRI approved herbicide is a mix of caprylic and capric acids and is a contact material that interferes with plant cells membranes causing leakage and desiccation.
It looked like a good fit for organic plasticulture systems such as strawberry that have wet weedy furrows which are difficult to access with mechanical tools because of proximity to plastic. We placed a trial in a very weedy field that also had one of the SoCal...
New Organic Herbicide Registration for California
Richard Smith, Farm Advisor
University of California Cooperative Extension, Monterey County
A new organic herbicide, Suppress, from Westbridge Company is now in the 30-day waiting period with the California Department of Pesticide Registration and should be fully registered by mid-February of 2015. The active ingredients are Caprylic and Capric Acids and were approved by the Organic Materials Review Institute (OMRI). It is a contact burn-down material that is registered for use in and around food crops including vegetables, trees and vines. I...
- Author: Cheryl A. Wilen
With summer kicking in, I thought it would be a good time to revisit organic herbicides. That's because most of these contact postemergent herbicides work better at higher temperatures than cooler temperatures. So to get the best bang for your buck and the accompanying satisfaction of seeing weeds practically die in front of your eyes (see photos below), summertime is optimal for using these herbicides.
Examples of organically labeled herbicides are listed below. There were a lot more a few years ago and some may still be registered such as GreenMatch and Matran but I cannot find them on the current product lists of the company that registered them.
Work by Tom Lanini and others has also shown...