The introduction of a new crop into a landscape brings certain unknowns, including the risk of drift from neighboring crops. Hemp is a new, high-value commodity that is now being produced in many parts of California. The attached document includes photos and descriptions of herbicide damage symptoms on hemp. Plants were sprayed with herbicides that are widely used during the hemp growing season. Materials were selected that are likely to be sprayed on commodities planted near, or adjacent to, a hemp field. The intention is to provide a brief description of herbicide injury expected from specific herbicides or similar modes of action. The final page of the document is a table with the common registered uses of the materials included in...
- Author: Brad Hanson
On January 22, 2020, the US Environmental Protection Agency (EPA) released the Interim Registration Review Decision on glyphosate.
Since this important herbicide has been a topic of considerable discussion in the past year (in fact, the report may have actually been released while I was attending a session focused on glyphosate at the recent California Weed Science Society conference with about 500 California weed managers), I'll post a few links to the EPA decision for those interested.
Here's a link to a good landing page for the Interim Decision...
- Author: Brad Hanson
A quick link to a Vineyard Team podcast and workshop series on weed control in California winegrape production systems
A couple weed control presentations of interest by weed science academics include:
- John Roncoroni "A new focus on weed management"
- Scott Steinmaus "Science and controversy of glyphosate"
In order to prevent herbicide damage in young trees, especially from postemergence herbicide, standard pomological practice is to apply white latex paint to the bottom 2 to 3 feet of trunk of newly planted trees, before applying herbicides. While this may provide some level of protection, research to support this practice is lacking. In order to assess the efficacy of white latex paint in mitigating herbicide damage, a field experiment was conducted in Arbuckle, CA to evaluate the impacts of latex paint on herbicide injury in young almond trees.
- Posted by: Gale Perez
From the Pests in the Urban Landscape blog :: Sept. 23, 2019
ANR: Agricultural and Natural Resources
UC ANR's charge is research and extension and we provide guidance about how to manage weeds using registered pesticides and by non-chemical methods. UC ANR includes information in its publications on how to effectively and safely use glyphosate where it is legal to do so as well as provide options for alternative chemical and non-chemical approaches for managing weeds.
UC ANR recognizes that the use of any pesticide carries risks,...