- Author: Brad Hanson
Several researchers in the UCD weed science program have been working on various aspects of glyphosate-resistant junglerice (Echinochloa colona) for the past few years. One of our undergraduate student interns, presented a poster at the 2018 Plant and Soil Conference (the California Chapter of the American Society of Agronomy) earlier this month in Fresno.
Drew reported on the (still in process) results of an experiment in which we grew seven populations of junglerice in growth chambers at 20, 30, and 40 C (~68, 86, 104 F) and treated them with a range of glyphosate doses (0, 0.5, and 1 lb ae/A). Drew, Sarah, and other lab members collected data on growth (biomass...
- Author: David Doll
- posted by: Brad Hanson
by David Doll, UCCE Pomology Farm Advisor (see also http://thealmonddoctor.com/)
With the emergence of herbicide-resistant weed populations, several perennial nut crop spray programs incorporate the use of pre-emergent herbicides. The correct use of these types of products provide the ability to control weeds for an extended period – sometimes into the late spring or early summer – reducing in-season burndown applications. When applying these products, proper application is critical to maximize weed control and the following points should be considered.
Herbicide selection. Pre-emergent herbicide selection should be based on the weed spectrum...
- Author: Brad Hanson
I received the information below regarding Zeus Herbicide (sulfentrazone) that is relevant to the California tree and vine market. The product was registered (supplemental label) for T&V in 2014.
Info from FMC (10/24/17):
As you work with your clients and make herbicide recommendations, please be aware that the supplemental labels for Zeus herbicide in California for many key crops have expired. Currently, growers may not apply Zeus herbicide on the crops included in the expired supplemental labels including grapes, lemon, orange, pistachio, walnut, tomato transplants and...
- Author: Brad Hanson
A quick post today to share a link to the recently revised "UC IPM Pest Management Guidelines for Walnut" (UC ANR Publication #3471). You can download the whole document as a pdf here, or use it online at the above link
Lots of great sections on management of non-weed pests of walnut, but since this is the Weed Science blog, here's the direct link to Integrated Weed Management section authored this time by:
- J. A. Roncoroni, UC Cooperative Extension, Napa County
- B. D....
- Author: Mariano Galla
Feather fingergrass, a summer annual weed native to warm temperate regions worldwide is becoming more and more common in the northern Sacramento Valley. It can be found in agricultural fields, orchards, roadsides and canals. This tuft forming grass, can be 1.5 to 2.5 feet tall and forms umbel like inflorescence: a cluster of short stalks originating from a common point, somewhat like umbrella ribs.
Feather fingergrass is a tough weed and it can be difficult to control. In addition, cases of glyphosate resistant populations have been reported in other countries and thus, unfortunately, it may develop resistance in California too.
I am planning to conduct some herbicide screening trials to evaluate control options and...