Northern 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 northern region present the developing nuts of the Nonpareil and Butte in the Chico/Durham area of Butte County and the Monterey in the Williams area of Colusa County.
With the exception of Tuesday and Wednesday, the 19th and 20th, when a weakening weather system spread from 0.25 to 0.5 inch of rain over the Sacramento Valley, bright sun and generally clear skies reigned over the region during the period, helping to push the develop crop ahead. Morning low temperatures were reported predominately in the 40’s with coldest readings reported in the mid and upper 30’s in the period’s closing days. Daily maximum temperatures exhibited a general cooling trend, with warmest readings recorded in the mid and upper 70’s as the period began. Readings then decreased daily, dropping into the lower 60’s under the influence of drying winds that reached in excess of 20 mph after the storm’s passage before rebounding into the lower 70’s under calmer conditions in the period’s closing days.
The passage of the storm during the past week failed to deter the growth and development of the 2013 crop in the Sacramento Valley. As witnessed in the photos accompanying this report, nut of all varieties are now well into the differentiation process, with observers reporting three and four sizes of nuts visible. The largest of these are growing well and will be retained to maturity while the smallest are being cut off from nutrients and will be dropped to the orchard floor. The generally good conditions the region has experienced since the completion of the bloom has promoted the growth of the developing nuts and will also help to increase the proportion of nuts retained by the trees.
Growers have been applying preventative fungicides in an effort to protect the developing crop and the newly emerged foliage. While disease pressure has been quite low this year, the rains received during the period did increase the potential for infection. Ironically, the rain did not provide enough water to reduce the need for irrigation and growers have been irrigating as required. Growers receiving their water from the federal Central Valley Project have been advised that deliveries will be limited to 75% of contracted amounts. Growers have also been busy applying foliar nutrient sprays and mowing excessive vegetation within their orchards.
Current weather at the National Weather Service
Photos: Dennis Meinberg and Ryan Christy, 3/25/13
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