Glyphosate is one of the most widely used herbicides in the world and is extremely important in many of our orchard, vineyard, and annual crops as well as in non-crop and home situations. However, it can be confusing to understand some of the differences among various formulations of glyphosate herbicides.

I'll paraphrase a recurring extension question as “I'm trying to compare the rates and cost-effectiveness of two glyphosate herbicides. One lists the active ingredient as ‘41% glyphosate as the isopropylamine salt' and the other as 48.7% glyphosate as the potassium salt'.  How do I compare these two herbicides?”

First important point, glyphosate is a weak acid...

A quick note to share a link to our (semi) regularly updated "Herbicide Registration on California Tree and Vine Crops".

Click here for a link to the PDF version on the Weed Research and Information Center page (this is probably your best bet for the most up-to-date version).  I've also attached the pdf version at the bottom of this posting as well as the low-resolution image right here.  --->

There were quite a few updates to this version compared to the last one I did in early 2016.  This reflects both real activity in label expansion as well as...

I found out today that I previously misread the label of a new herbicide registered in several California orchard crops. 

Broadworks Herbicide (from Syngenta) was registered in fall 2015 on several citrus, stone fruit, and tree nut crops (but not every crop in those groups). 

I'm not entirely sure if I misread the label or if I simply made a typo when I last updated the T&V Herbicide Registration chart (which is totally possible after you've read several dozens of labels).  At any rate, I erroneously listed mesotrione as registered on peach in my November update of that chart; however, Broadworks is not actually currently registered on that...

I thought I'd share a link to a YouTube channel from the Ohio State University Weed Science program. 

There is a series of short time-lapse videos of several herbicides acting on different weed species.  Includes paraquat (a PSI inhibitor), fomesafen (a PPO inhibitor), atrazine (a PSII inhibitor), glyphosate (an EPSPS inhbitor), quizalofop (an ACCase inhibitor), cloransulam (an ALS inhbitor), 2,4-D (a synthetic auxin) and glufosinate (a glutamine synthase inhibitor. 

Cool videos (assuming you like watching plants die agonizing deaths, of course...)

Click here: Herbicide Injury - Time-lapse Mode of...