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...
- Posted by: Gale Perez
Diagnosing Herbicide Symptoms 2018
July 10-11, 2018
Bowley Plant Science Teaching Center, UC Davis
Weed scientists at the University of California are offering the Diagnosing Herbicide Symptoms 2018 course on July 10-11, 2018. This 1-1/2 day course will focus on how an herbicide...
- Author: Brad Hanson
Today, I thought I'd share a set of photos from a herbicide symptomology demonstration that I conducted in fall 2013 for our UC Weed Science School (next scheduled for fall 2015) and more recently in spring 2014 for a training session with other UC Cooperative Extension personnel.
For those of you that work regularly with herbicides of different modes of action this may be old-hat. However, many of us who get questions about herbicide injury in the field don't get always get to see comparisons under controlled conditions.
A few definitions, caveats, and brief explanations of the attached slides:
- MOA = Mode of Action...
- Author: Oleg Daugovish
Growers and pest control advisors look at strawberry plants daily and see problems often. Some problems like salt injury are frequent while others, like frost injury are only seen once in a few years. With over 60 pathological, physiological and nutritional problems it is important not to overlook injury from herbicides. In collaboration with UC strawberry workgroup members we recently launched a bi-lingual web site that displays injuries and disorders from chemical and other causes.
The site is a work in progress as we continue to add images of problems, translation into Spanish and update the content of existing pages with new information. We hope that with improved access to images and descriptions the site can be useful in...
- Author: Carl Bell
- Posted by: Gale Perez
A recent blog post titled–Plant growth and development and herbicide efficacy discussed herbicides like glyphosate and imazapyr that move through plants in the sugar conducting tissues (aka phloem or symplastic system).
There are some herbicides that move in the water conducting tissue (aka the xylem or apoplastic system). These herbicides, mostly in older classes of chemicals, enter plants through the roots and travel upward to the leaves where you see their effect. Many of these herbicides are only used in crops, so it is unusual that anyone working in a natural area will ever encounter them.
Others, such as diuron or bromacil are used to some in roadsides, under pavement, industrial areas, railroad beds, and...