Southern California - March 25, 2013
This report covers conditions and observations made between Saturday, March 16 and Sunday, March 24, 2013. The next report is scheduled for Monday, April 15, 2013. However, in the event of any significant occurrences prior to that date, this site will be updated as soon as possible.
This report’s photos for the southern region show the developing nuts of the Sonora in Madera County, followed by the Nonpareil and Fritz in Kern County.
Temperatures moderated during the period as a weakening weather system brushed against the region. Morning low temperatures were reported predominately in the 40’s with warmest readings reported in the low to mid 50’s on Wednesday the 20th as the insulating clouds from the approaching storm system covered the region. Winds with speeds in excess of 20 mph helped to dry the air after the storm’s passing and allowed minimum temperatures dip into the mid 30’s on Saturday, the 23rd. Daily maximum temperatures were reported at their warmest levels early in the period, when reading reached into the mid and upper 70’s. Readings gradually decreased into the mid and upper 60’s under the influence of the weakening weather system that dropped trace amounts to a few hundredths of an inch from Madera, south to Tulare County late in the day on Tuesday, the 19th and the winds that followed the storms passage. Warmer conditions returned to the region on the period’s closing days as temperatures reached into the lower 70’s.
As may be seen in the photos accompanying this report, nuts of all varieties are developing well under the generally beneficial weather the region has experienced since the completion of the bloom. All varieties are well into the differentiation process, wherein the nuts divide into several sizes with the largest shedding their jackets and being retained to maturity while the smallest are shed from the trees.
The forecast of rain during the period inspired some in the region to add preventative fungicides to their foliar nutrient sprays in an effort to prevent fungal infections on the developing nuts and foliage. The generally beneficial conditions the region has experienced this year has resulted in very low disease pressure, leaving the crop virtually disease free while allowing growers to eliminate additional fungicide treatments. While growers do not like to see excessive winds that can lower dew points, promoting dangerous morning temperatures or damage the trees themselves, one fringe benefit of the winds experienced over the past week has been to help scrub spent petals and drying jackets from the trees, further reducing the potential for fungal disease.
Growers have been actively irrigating their orchards and will continue to do so. The U.S. Bureau of Reclamation has announced water deliveries from the federal Central Valley Project have been reduced to 20% of contracted amounts. Meanwhile, deliveries from eastside districts have yet to begin, leaving growers fully dependent on privately owned deep wells for their irrigation needs. In between irrigations, sprayers can be found applying foliar nutrients while mowers reduce excessively tall weeds growing within the orchards.
Current weather at the National Weather Service
Photos: Ernie Reichmuth and Gerald Guthrie, 3/25/13
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