- Author: Andrew Johnson
- Author: Marcelo Moretti
- Author: Brad Hanson
Several field experiments were conducted to evaluate the performance of pre-emergence herbicides, herbicide rates, and tankmix combinations at different locations in the Central Valley of California and to compare the efficacy of burndown herbicides in mixture with different pre-emergence herbicides. The same treatments were used in three studies located in Fresno, Merced, and Colusa counties. Only data from the Merced county site is presented due to low weed densities at the Fresno and Colusa county sites.
The experiment was conducted in a mature almond orchard with solid-set sprinkler irrigation, and very sandy soil (95% sand) near Delhi, CA. Treatments were applied on February 10, 2012 using a CO2 pressurized back pack...
- Author: Brent A Holtz
- Author: Mick Canevari
- Posted by: Gale Perez
In June we visited a first-leaf almond orchard that had started the season growing normally, but as the root system expanded, the trees’ growth became rapidly stunted (Fig. 1). The newly expanding shoot tips showed ‘little leaf’ symptoms (Fig. 2) characteristic of glyphosate injury, with an incredible proliferation of shoots (Fig. 3) growing from the same point on the scaffolds.
After investigating crop rotations, we learned that the trees showing symptoms had followed alfalfa newly planted the previous year that had been removed after only one year. Trees from the same nursery and farmed by the same grower were planted on the other half of the ranch in ground following three years of alfalfa...
- Author: Brad Hanson
Last Thursday (July 19th) was the 56th annual UC Weed Day at the Davis campus.
We had a really good turnout again this year with just under 150 participants including weed science researchers, students, farmers, land managers, pest consultants, and government agency people in attendance. Cooperative Extension Specialist Tom Lanini organized the morning field tour and afternoon presentation session and ordered up really great weather for the day.
We started out on campus for registration and signing up for various continuing educaton credits before heading out on two buses and a parade of trucks and vans to the...
- Author: Brad Hanson
Today I thought I'd share a recent research report on the the phenomenon of "enhanced" degradation of the herbicide simazine in citrus orchard soils. Click here for a link to the publication in the open-source journal, Air, Soil, and Water Research (Abit et al. 2012. Air Soil and Water Research 5:69-78). The lead author was a UC Davis post doctoral researcher and her coauthors include UC Davis, USDA-ARS, Fresno State, and UC Cooperative Extension folks.
This work was started several years ago in response to some questions from San Joaquin Valley orchard and vineyardists poor weed control with simazine. They suspected herbicide...
- Author: Brad Hanson
UC Cooperative Extension Farm Advisor David Doll is organizing a "Central San Joaquin Valley Summer Almond Field Day" on June 1, 2012. More info HERE or in the agenda at the bottom of this post.
As a part of a diverse almond research agenda that David has put together, we'll be discussing the results of several current herbicide efficacy experiments that my groups is conducting at this site as well as other locations in the state. The primary herbicide experiment that we'll discuss includes a number of residual herbicide comparisons including various rates and tank mixes of Alion, Pindar GT, Prowl, Trellis, Rely, Surflan,...
