February 2, 2015

This report covers observations and conditions just prior to the start of the 2015 bloom. We anticipate posting the first of the daily Bloom Reports sometime during the second week of February.

This report’s photos for the central region provide a glimpse of the activities going on in the Ripon area of San Joaquin County. First, a backhoe preparing an orchard for planting, while nearby, a mechanical planter sets the trees into the orchard berms. Our final image shows an example of the amount of mummies being shaken from the trees after the 2014 harvest, while today’s featured image shows a grower spreading compost in his orchard.

Following several days of soaking rain during December, when a series of vigorous storm systems dropped from 3 to 7 inches of rain across the region, January’s weather proved quite disappointing  with a total lack of rainfall  producing the driest January in recorded history. While rainfall totals have been disappointing, the scene in the Sierra Nevada watershed is even more ominous. The snowpack needed for the summer irrigation season is reported at very low levels, approximately 25% of seasonal normal. Combined with equally low storage levels in the region’s reservoirs, all in the region are concerned about the ability to meet irrigation requirements during the coming growing season.

If there is a good side to the region’s weather, it may found in the return of foggy conditions promoted by December’s rain. While hazardous for the region’s drivers, the fog provides the best conditions required to remove “mummy” nuts remaining in the trees following the 2014 harvest. And observers are reporting that there are plenty to be removed. A by-product of the drought conditions the region has endured over the past few years has been “sticky” conditions in many orchards that prevented the trees from releasing all of the crop during harvest. The lack of winter rain and fog in past years has also produced very poor conditions for removal of the mummy nuts. As a result, populations of Navel Orange Worm over-wintering in the nuts have increased and quite a few growers endured significant damage in the 2014 crop. Growers have taken advantage of the fog and have sent shakers, sweepers and mowers into the orchards during January to destroy the mummies and the over-wintering larvae living within.

Growers have spent the past few weeks preparing for the upcoming bloom. In addition to planting new trees, growers have been shredding previously pruned brush, fertilizing and applying dormant season disease treatments intended to prevent fungal organisms from affecting the new crop. Many have also been applying gypsum and compost materials to enhance soil conditions within the orchards. A number of growers who have water available from their private well have also started irrigating in order to ensure optimal moisture conditions as the trees awaken from their winter dormancy. While the rainfall received in December was a very good thing, January’s lack of moisture has translated into less than optimum moisture levels in many areas of the region.

As this report is being prepared, flower buds in advanced Sonora plantings are entering the early green tip stage, with single trees in isolated locations starting to present a few open flowers. While the more stable temperatures experienced in areas with heavier, longer lasting foggy conditions has slowed development in those locations, buds in the Nonpareil  and California type varieties are swelling nicely, with the most advanced examples just beginning to move into the green tip stage.

Current weather at the National Weather Service
Mel Machado and Matt Visser
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