Southern California - July 1, 2013
This report covers conditions and observations made between Monday, June 3 and Sunday June 30, 2013. The next report is scheduled for Monday, August 5, 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 present the splitting nuts of the Nonpareil in Madera County, followed by an example of the web spinning mites that have infested many orchards in Tulare and Kern County. Our final image shows evidence of the salt burn observed on the Fritz variety, also in Kern County.
Widely varying temperatures were reported throughout the southern region during the June transition from Spring into Summer. The period’s opening days brought a spike in maximum temperatures as readings climbed from the upper 80’s and lower 90’s, reaching to as high as 108 degrees by Saturday, the 8th. Readings then dropped dramatically over the next two weeks, ranging from the upper 70’s to upper 80’s. Following a particularly significant cooling period between the 23rd and 25th when an unusual winter-like storm passed over the northern and central regions, readings recovered quickly as a dry, stable air mass settled over the state, driving temperatures to as high as 108 degrees throughout the region, setting a few new records. Morning lows for the majority of the period ranged between the upper 50’s and lower 60’s. However, most notably during the period’s hottest days, minimum temperatures dipped only into the upper 70’s in the coolest locations.
Water supplies have become a prime concern among growers in the southern San Joaquin Valley. Water deliveries from the Chowchilla and Madera Irrigation Districts began during the month, providing some degree of relief for grower’s deep wells in those areas. However, the Fresno Irrigation District has announced that it will curtail deliveries to its Fancher and Dry Creek Divisions at mid-July. Observers are reporting that growers in the Madera and Fresno Districts anticipate having surface water available until harvest, but will have to resort to their private wells to complete the growing season. Deliveries to those drawing their water from the federal Central Valley Project remain at 20% of contracted amounts. Ominously, these growers have also been told that if the state receives only a normal snowpack during the upcoming winter, there will be no deliveries during the 2014 irrigation season. Growers in the federal system typically transfer water from fallowed lands they own in order to help meet their crop needs. However, should the threat of a “zero” allocation come true, no transfers will be possible next year and growers will be totally reliant on their privately owned deep wells. Growers continue to service existing wells as their pumping levels drop. Drillers report that they are extremely busy, servicing existing wells as well as preparing new sites, particularly in the Madera County area.
Water quality is also become a bit of an issue under the pressure of rising salinity levels recorded in grower’s private wells. As visible in the third of this report’s photos, observers have noted increasing leaf burn in salt sensitive varieties.
As shown on the first of this report’s photos, observers have noted the start of the Nonpareil hull split. Treatments to control Navel Orange Worm, NOW, began in the Kern and Tulare County areas on the 20th, with growers farther to the north following shortly thereafter. Growers are also monitoring soil moisture levels closely as they work to withhold irrigation to one-half of consumptive use for a two week period in an effort to reduce the incidence of fungal hull rot infections, while not imposing undue stress on the trees. This delicate balance is made much more difficult by the heat wave currently enveloping the entire Central Valley.
Observers are reporting that growers in the Madera and Fresno County areas have had relatively few difficulties with web-spinning mites, with a few orchards having populations building to levels requiring treatment. The same cannot be said for those in the Tulare and Kern County areas, who have been engaged in a pitched battle. Observers are reporting that growers there have been unable to adequately control infestations and many plantings are covered with webbing, as may be seen in the second of this report’s photos. Growers report that dust covering the trees as a result of the winds the region has experienced this year has reduced the efficacy of miticide treatments and allowed populations to grow to damaging levels. Some have had to make multiple treatments to prevent their orchards from being defoliated.
The next few weeks will find growers completing final pre-harvest preparations. Observers are reporting that shaking of the first orchards to be harvested should begin prior to the end of July.
Current weather at the National Weather Service
Photos: Ernie Reichmuth and Gerald Guthrie, 7/1/13
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