Cross post from the UC Weed Science blog 11-21-14
Effective this fall (2014) there will be a fairly significant change to the Alion herbicide label for California orchard and vineyard crops. Growers and PCAs will want to be aware of this as you’re planning your dormant-season herbicide programs now that many areas of the state are getting some rain.
The use patterns for Alion (active ingredient: indaziflam) has been modified for tree nuts, grapes, stone fruit, pome fruit, and olive (citrus uses were not changed). Read More
Posted by David Doll
/ November 14, 2014 / Posted in Almond
/ 6 Comments
An earlier post discussed proper soil sampling methods. By now, those results should have been received and reviewed.
A winter leaching program will help reduce the occurrence of tissue toxicity in the growing season.
Almond trees are relatively sensitive to sodium, chloride, and boron. Yields are impacted when average root system salinity increases above 1.5 dS/m, with research indicating a 19% decrease in potential yield with every 1.0 dS/m increase. This yield reduction is due to the osmotic effects of the salts, which basically makes the tree “work harder” for water reducing growth and vigor. If excess salts continue to accumulate within the rooting zone, trees will ultimately uptake the salts and cause tissue toxicity. The salts of primary concern are sodium, chloride, and boron. A leaching program should be implemented when EC of the entire rooting depth exceeds 1.5 dS/m or sodium, chloride, and boron exceed an exchange saturation percentage of 5%, 5 meq/l, and 0.5 mg/l, respectively. Read More
Posted by Katherine Pope
/ November 08, 2014 / Posted in General
/ 2 Comments
Katherine Pope, UCCE Farm Advisor Sacramento, Solano and Yolo Counties
Part 1 of 3 in the series – What can we learn from the low chill winter of 2013-2014
Example of decreased chill accumulation at one site
With harvest wrapped up, it’s a good time to take stock of the impacts of the warm winter of 2013-2014. Average chill was down 25% in the Central Valley, falling behind in January and never catching up. Orchards in many crops showed classic symptoms of low chill – delayed and extended bloom, poor pollinizer overlap and weak leaf-out. Prolonged bloom likely resulted in some cherries, pistachios and prunes experiencing warmer bloom temperatures, which decreased yields for many. Drought-related water stress likely contributed to some of the yield, size and quality issues we saw at harvest. But low chill was almost certainly responsible for a great deal of the unusual tree behavior, low yields and poor quality. So what can we learn from this tough year moving forward?
Posted by David Doll
/ October 27, 2014 / Posted in Almond
/ 2 Comments
Rootknot Nematode on roots (Photo: David Doll)
Late fall is a good time to consider nematode sampling. Sampling may be important to perform if lack of vigor or poor growth is observed within an orchard. Samples should be taken once the soil begins to cool in October. For best results, multiple soil samples should be taken, with a minimum of one sample per soil type present in the orchard. If soils are relatively uniform, two to three samples should be made for fields smaller than 60 acres. Five or six samples are needed for for larger uniform fields. A composite of 5-7 different spots within the soil type or field quadrant should be pooled (mixed and combined) as one “sample.” Soil samples should be taken at a depth of 15″-20″ within the rootzone of the tree. Once enough samples have been collected, they should be placed in a properly labeled bag, kept cool and out of the sun, and submitted to a lab to conduct the nematode analysis. Read More