This report covers conditions and observations made between Monday, May 26 and Sunday, June 29, 2014. The next report is scheduled for Monday, August 4, 2014. 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 the early hull split of the Nonpareil in the Escalon area of San Joaquin County, followed by the more advanced split found in the Westley area of Stanislaus County and the salt injury found in a Butte and Padre planting west of Newman near the Merced/Stanislaus County line.
While dry conditions dominated the weather during June in the northern San Joaquin Valley, temperatures during the period varied considerably, from comfortably mild to seasonably hot. Daily maximum temperatures were reported predominately in the low 80’s to the low 90’s, with readings reaching their maximum level in the upper 90’s to as high as 105 degrees on June 8th through the 10th. Morning minimum temperatures followed a similar pattern, ranging from the low to mid 50’s to the mid 60’s each morning.
Breezy conditions continued to confound growers on many days during the month. While wind speeds for the most part remained below 10 mph, speeds reached in excess of 20 mph on several occasions, increasing water consumption and raising clouds of dust into the air. Windiest conditions accompanied a very weak weather system that passed over the northern half of the state on Thursday, the 26th, dropping from trace amounts to a few hundredths of an inch of rain over the San Joaquin and northern Stanislaus County area during the nighttime hours.
Water supplies dominated the growers’ thoughts and words during the period as they worked to support their orchards and the developing crop. While growers in much of San Joaquin County have enjoyed better water supplies than those in other areas of the region, many growers in all areas have struggled to one degree or another to provide adequate irrigations to their orchards. As a result, signs of stress have manifested themselves in many plantings around the region, both from inadequate quantities of water as well as from the use of poor quality water. This was noted in the last report for this region. However, stress levels have intensified as the crop matures. The most typical symptoms observed are the lack of new spur growth in the tree canopy, the cessation of growth in orchards that received adequate water supplies earlier in the season and have now been cut back, as well as leaf burning and defoliation in plantings receiving water with excessive salinity levels. The degree of symptoms varies greatly across the region, with areas along the west side of the region presenting the greatest measure of symptoms.
Crop development continues to progress, with hull split in stressed Nonpareil plantings first observed during the week of June 16th along the west side of the region. Hull split has progressed across the region, and observers are now reporting splitting in all areas, approximately 7 days ahead of last year. Growers have been monitoring their orchards for signs of split and the life stages of the Navel Orange Worm in order to promote the best timing of treatments required for control. Now that the split has begun, growers began sending spray rigs into the orchards during the final week of the period. Treatments will follow the progression of the split throughout the balance of the region’s Nonpareil plantings. The lack of adequate rainfall over the past winter resulted in very poor conditions for mummy shaking, the prime method of reducing the amount of worms in the orchards and the potential for damage to the subsequent crop. Treatments at hull split are therefore the last chance to reduce crop losses and the level of contamination in the harvested crop.
Growers also spent much of the period ensuring that their orchards and equipment are ready for the upcoming harvest. Given the current pace of development, observers are estimating that growers will begin shaking of the first, more stressed orchards on the west side of the region during the week of July 20th.