- Author: Bradley Hanson
I learned recently that the preplant incorporated (PPI) herbicide ethalfuralin (Sonalan HFP) was labeled for use in hemp and stevia. See below for the CA/NY supplemental label or download it from your preferred label website.
The use petition was submitted to US-EPA by the IR4 program (see EPA docket EPA-HQ-OPP-2021-0130 at www.regulations.gov if you're into that kind of thing).
This herbicide is as WSSA Group 3 herbicide that is usually applied to the soil before planting and incorporated into the soil with mechanical methods or irrigation. After incorporation, the crops can be seeded or transplanted at a sufficient depth that the crop roots grow beyond the treated zone.
Ethalfluralin is pretty widely used in crops like dry pea, dry bean, peanut, safflower sunflower etc. and controls many annual grasses and broadleaf weeds. Importantly, this the only PPI herbicide registered in hemp or stevia in California so it will undoubtedly be a good addition to the very limited weed control toolbox in those crops.
Sonalan HFP CA NY1d Supplemental Label-1
- Author: Bradley Hanson
One of the largest weed issues affecting the California processing tomato industry is the parasitic plant, branched broomrape (Phelipanche ramosa; Orobanche ramosa)
- https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=50241
- https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=47701
- https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=43342
Last week, CDPR issued a positive decision on a 24c "Special Local Needs" label request to allow application of rimsulfuron (Matrix SG) via chemigation through subsurface drip irrigation systems. This newly-allowed use pattern should be helpful for suppression of broomrape in tomato.
The CDPR decision was posted here: https://www.cdpr.ca.gov/docs/registration/nod/nodmenu.htm and is in Report 2022-39 for the Week of September 30, 2022. I've also attached it to the bottom of this blog post.
Rimsulfuron is widely used in tomato in California both as PRE and early POST herbicide for control of many weeds. The 24c label simply adds a new application method that is targeted specifically at the broomrapes which are parasites that attached to the root of tomatoes and other host plants. The new use pattern puts the herbicide right in the rootzone of the tomato plant at the time when broomrape seeds are germinating and the seedlings just attaching to the host.
The protocol for this specific use is three applications of rimsulfuron; one at early bloom and two more at 10-15 d intervals thereafter. Each of the three applications should be 1.33 oz product (25% WDG) which equates to the yearly max allowed on the Section 3 label.
In our field trials, chemigated rimsulfuron provided significant reductions (about 4-fold) in broomrape clusters in a highly-infested field; however, no herbicide treatments were 100% effective for this A-listed quarantine pest. This may be of interest and utility to processing tomato growers who have light infestations or fields near infested fields that may be at some risk but should be combined with other sanitation practices.
One important note is that this SLN cannot be used with other rimsulfuron applications. The 4 oz product per year maximum is for all uses; so, if you apply rimsulfuron via chemigation for broomrape management, you cannot also use rimsulfuron for PRE or POST control of other weeds.
CDPR 24c decision rimsulfuron broomrape
- Author: Brad Hanson
"A Virtual Conference to Discuss Real-World Weeds".
That's a great tag-line for the California Weed Science Society conference and a sign of the times.
Even though our in-person interactions as weed researchers, managers, and regulators has been put on hold this year, weed control goes on and so does the need for the education and updates provided by the CWSS.
Please remember to register for the conference this year to keep up your education and training and get the latest information as well as supporting YOUR California Weed Science Society. The program committee has put together another high-quality program that touches on the many aspects of weed science in California.
Here's the link to the registration page:
While there is a lot of value in our normal in-person 2.5 day conference format, there are a few benefits of the online format.
- You can view the sessions at your convenience since they are prerecorded. In a state like California, there's no "off-season" for everyone and in this format you don't have to dedicate 3 days to get this great content.
- We have several registration options if you don't want to participate in the whole event. Of course it's a better deal (per credit) if you register for the full program, but there are several options if you just want the Laws and Regs, or just the breakout sessions, etc.
- No travel expense! If you've been CWSS-curious but have not been able to justify the time or expense of the travel in the past, this is your opportunity!
- Lastly, this may be a one-time opportunity to see weed science experts from around California and the US delivering cutting-edge research updates while wearing sweatpants and broadcasting from the spare bedroom in their house while their dog barks at the mailman - what an opportunity! (just kidding, we actually have high quality professional video and audio and on-demand retrieval of the presentations).
The content will be available online from January 25 through February 26. Register early before the price goes up!
Here's how to get to the registration page:
Here's the current program agenda:
I'll see you on the internet in January-February 2021 and, hopefully back in person for CWSS 2022!
-Brad
/span>- 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 and related information.
Here's a direct link to the Glyphosate Interim Registration Review Decision
This landing site has links to drill further into: the Federal Register Notice, the Interim Decision, response to public comments, and an updated review to two recently published epidemiology data sets.
Interesting and useful information from a scientific regulatory perspective.
Brad
When you hear the term “pesticide,” what comes to mind? Do you understand what pesticides are and, more importantly, how to use them correctly?
A pesticide is any material (natural or synthetic) used to control, prevent, kill, suppress, or repel pests. “Pesticide” is a broad term that includes insecticides, herbicides (weed or plant killers), algaecides (algae and moss), fungicides (plant diseases), rodenticides, miticides (mite control), and molluscicides (snails and slugs). Even antimicrobial products (such as bleach and sanitary wipes) that kill bacteria on surfaces and chlorine added to pools are pesticides. If a product has a U.S. Enviromental Protection Agency (EPA) Registration Number on its label, it is a pesticide. To make it more confusing, there are some pesticide products that are exempt from registration and won't have an EPA Registration Number.
Home-made mixtures that you make yourself to kill or repel pests are also technically considered pesticides. These include dish soap and water, garlic juice spray, hot pepper spray, vinegar and water, and many other such concoctions.
In future issues of the Retail IPM newsletter and this blog, we will discuss several pesticide topics, including the difference between organic, less toxic, and more conventional pesticides, what are “exempt” pesticides, using pesticides safely, pesticide storage and disposal, and reading and understanding labels.
For more information about pesticides, see the UC IPM Pest Notes: Pesticides: Safe and Effective Use in the Home and Landscape. To sign up for the newsletter, visit https://ucanr.edu/survey/survey.cfm?surveynumber=11686.