Central California - August 6, 2012
This report covers conditions and observations made between Monday, July 2 and Sunday, August 5, 2012.
The next report is scheduled for Monday, September 3, 2012. 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 central region present a shot of a mid-night hull split treatment to control Navel Orange Worm west of Modesto, followed by the hull split of the Nonpareil variety in the Gustine area of western Merced County and the first Nonpareil shaken in the Newman area of Stanislaus County.
Monsoonal moisture at mid-month and again during the final weekend of the period provided contrast to the clear skies that dominated the central region’s weather during July. Morning low temperatures exhibited the greatest stability, with readings widely reported in the 50’s, rising into the 60’s on the warmest mornings. Daily maximums varied more significantly, with highest readings reported in the upper 90’s to just over 100 degrees. However, readings dropped into the mid and upper 70’s at mid-month, under the influence of the cloudier skies that accompanied the monsoonal flow approaching from the south. The mid-month flow of moisture generated widely scattered showers throughout the region, producing only trace amounts of rainfall, while the cloudy skies that covered the region on Saturday, August 4th failed to produce more than a few drops of rain and a bit of lightning.
Weed control, irrigation and pest management dominated the period’s activities as growers worked to ensure that their orchards are ready for the approaching harvest. Observers are reporting that a significant number of the orchards are exhibiting signs of water stress, apparently due to depleted moisture reserves deep in the soil profile. The stress has been exacerbated by grower’s normal practice of reducing irrigations during the first two weeks of hull split in an effort to reduce the impacts of fungal infections on the moist hulls as they open. Growers have been sending flail mowers into the orchards to reduce vegetation and sprayers to control Navel Orange Worm. While many are reporting very low trap counts, those with indications of a potential infestation have been treating to prevent serious losses. As can be seen in the accompanying photo, sprayers worked throughout the night to take advantage of cooler temperatures and calmer air. Growers have reported increasing mite populations in orchards around the region. While not widespread, some have been forced to treat orchards where populations have increased to economically damaging levels. Those with growing ant infestations have also been completing bait applications in an effort to reduce populations below economically significant levels.
Observers are reporting that the hull split of the Nonpareil is progressing well and that the orchards are in generally good condition, other than the previously noted water stress. However, a few have also noted leaf burning caused by excessive salinity in their irrigation water.
As is normally the case, orchards along the west side of the region will be the first harvested. While a few orchards in the Newman and Westley area were shaken on the 27th and 28th, many west side growers opted to provide their orchards with an additional irrigation and are expecting to send shakers into the orchards during the first full week of August. Growers along the Highway 99 corridor and along the east side of the region are expecting to begin shaking sometime between August 13th and 20th. In addition to the Nonpareil, observers are also reporting that hull split is now visible in Sonora, Carmel, several California types, Butte and Padre.
Unlike last year, grower’s attention to disease control earlier in the growing season has largely prevented a repeat of the serious Rust and Scab infestations that prematurely defoliated so many orchards last year. However, some have noted an increasing number of orchards impacted with Lower-Lim Die Back, LLDB. While the cause of this disorder is not fully understood, University researchers believe that there may be a connection with excessive water levels in the top inches of the soil profile early in the growing season.
As this report is being prepared, huller/sheller operators are also completing pre-harvest preparations and stand ready to begin their season as soon as product arrives from the orchards.
Current weather at the National Weather Service
Photos: Mel Machado, 8/6/12
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