This report covers conditions and observations made between Monday, March 31 and Sunday, April 27, 2014. The next report is scheduled for Monday, May 26, 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 a cut-away view of the Nonpareil and an example of the pale green to yellow tint imparted on an orchard irrigated using high pH ground water, both in the Newman area of Stanislaus County. Our final image shows the tell-tale signs of an infestation of the Leaf-Footed Plant Bug in the Roberts Island area of San Joaquin County.
Wet conditions bracketed the central region’s weather during the period, with rain falling in the period’s opening and closing days. Morning low temperatures remained above threatening levels throughout the month, with minimum readings generally warming during the period from the upper 30’s and lower 40’s to the upper 40’s and lower 50’s. While minimums did cool slightly in the period’s final week as a fairly potent weather system passed through the state, no danger of frost was created. Daily maximum values increased quickly during the first week of the period, rising from the upper 50’s and lower 60’s to the upper 70’s to mid 80’s where they remained until the period’s final days.
Official rainfall totals from the region’s two weather events varied between 0.5 to 1.0 inches. However, growers in the Ripon area of San Joaquin County and Salida area of Stanislaus County reported receiving as much as one inch of rain during a particularly strong downpour on Friday, the 25th bringing their total for the period to as much as 2.0 inches. Growers in these areas also reported hail up to ½ inch in diameter, which caused some damage to nuts exposed to the sky.
Crop development has progressed at a fairly brisk pace in the northern San Joaquin Valley over the month, under the influence of the generally above normal temperatures the region has experienced. As shown in the photo accompanying this report, Nonpareil nuts along the west side of the region have reached their full size and have begun to solidify. While the date at which the first nuts are fully solidified will provide the best reference of maturity and an indication of the start of the harvest, growers and observers believe that the crop is running approximately one week ahead of last year. However, as a comparison, growers in the Patterson area of Stanislaus County have begun harvesting apricots two weeks ahead of last year.
In the pest management arena, growers in the San Joaquin Delta, where approximately 1,200 to 1,500 acres of almonds have been planted in recent years have noted damaging infestations of Leaf-Footed Plant Bugs feeding on the Aldrich and Fritz varieties. This insect caused significant losses in individual orchards near the eastern foothills in 2013 and has been reported in some eastside plantings again this year. Growers in all areas of the region also reported isolated cases of pseudomonas bacterial infections on the Padre variety, which was causing a slight degree of leaf loss. Special attention is being given to the number of Navel Orange Worm adult males being caught in the new pheromone trap, now in its second year of use. Growers and Pest Control Advisors are running the new traps alongside of the traditional egg trap, designed to monitor egg laying by female moths as they work to learn how to employ the new pheromone trap to monitor insect populations and life cycles.
Water remains the prime consideration of growers throughout the region. Deliveries from local irrigation districts began during the period, with farmers in the Turlock Irrigation District seeing their canals filled on April 10 while those in the Modesto District were able to receive water on April 15. Growers in the Merced Irrigation District did not receive their first deliveries until April 21 and will receive only a six inch allocation this year. During the final week of the period, management of the State Water Project increased its allocation to growers from zero to 5% of contracted amounts. Most believe that the increased allotment will help only those growers north of Fresno and even then not significantly as the water will not be available until after September 1.
Obviously, many growers are highly dependent on privately owned deep wells for their water this year. In addition to being quite expensive, ground water can also be of questionable quality, with the most serious problems presented by high pH and dissolved salts. As may be seen in the second of this report’s photos, high pH water can create a significant yellowing of the leaf tissue as the excessively alkaline water ties up the nutrients needed for crop development. In addition to the rather striking color, these orchards are exhibiting a lack of spur development.
Growers in the most severely impacted areas are managing what water they do have very tightly. For some, rather than managing with an eye towards maximizing yield, the goal has become to maintain the orchard and keep the trees alive. Some plantings are already exhibiting moderate signs of stress as their owners implement deficit irrigation strategies.