Managing junglerice in tree nut crops – a summer grass weed resistant to glyphosate

Posted by Brad Hanson  /   September 30, 2014  /   Posted in Almond  /   No Comments

Cross posted from the UC Weed Science blog and originally written for the California Weed Science Society Research Update and News. -Brad

Managing Junglerice in Tree Nut Crops – a summer weed resistant to glyphosate

Marcelo L. Moretti1, Seth Watkins1, Bill Gary2, and Brad Hanson1

1University of California – Davis, CA; 2Mid Valley Ag – Linden, CA

Junglerice, or Echinocloa colona, is a summer grass commonly found in orchards, annual crops, and roadsides of California. This weed germinates in early spring and throughout the summer and can grow and reproduce quickly. Junglerice commonly is identified by purple bands on the leaves.  However, in some populations or environmental conditions these stripes are less visible; thus a lack of banding should not be used as a definitive means of identification. In recent years, the feature that makes this summer grass really stand out in California fields is the discovery of glyphosate-resistant populations. Read More

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Fall soil sampling for salinity management

Posted by David Doll  /   September 29, 2014  /   Posted in Almond  /   2 Comments
Photo courtesy of Bill Ray.

Photo courtesy of Bill Ray.

The harvest season is winding down, and in the next few weeks many orchards will be receiving their last irrigations. After the final irrigation of the season, growers should conduct soil sampling to determine any potential issues with sodium, chloride, or boron. These salts are “imported” onto the farm through fertilizers and soil amendments, with the largest amount coming through irrigation water.

There are several videos online that go through the procedure of collecting a soil sample. Here is a link to an article containing this series. When soil sampling for salinity management, varying depths of soil must be collected to determine where the salts have accumulated. Suggested depths are in one foot increments (down to four five feet), but 18 inch increments may also be used. If dealing with soil infiltration issues, it may be of value to sample the top 6″ to determine if there is a soil imbalance.

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Scale and Lower Branch Dieback in Almonds

Posted by Gurreet Brar  /   September 13, 2014  /   Posted in Almond  /   4 Comments

Gurreet Brar, UCCE Farm Advisor (Nut Crops), Fresno & Madera Counties

Lower branches killed by high populations of scale (Photo by Gurreet Brar).

Lower branches killed by high populations of scale (Photo by Gurreet Brar).

This summer we observed many cases of lower branch dieback in almond trees (like the one shown in picture). In many cases these symptoms were found to be associated with high scale populations. Diagnosis of such branches revealed that San Jose Scale and Walnut Scale caused lesions beneath the bark resulting in death of the tissue. These scales suck plant juices from the inner bark by inserting their mouthparts into twigs and injecting a toxin. When the populations become high enough, the numerous lesions may coalesce and cause the whole branch to die. Uncontrolled populations can kill branches within 1-3 years. San Jose Scale can be found on most, if not all, almond varieties. Walnut scale seems to like Monterey variety more than the others. Read More

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