Blue Diamond Growers Crop Progress Update Report for March
Observers are reporting that crop development increased dramatically in all regions under the influence of the warm conditions experienced during the first week of the period. As seen in the photos accompanying this report, nutlets have been differentiating in size, with the largest breaking free from their protective jackets. Leaf cover on the trees has also developed vary rapidly, allowing the trees to begin pulling nutrients and water from the soil. The trees have also begun the normal process of casting the smallest nutlets to the ground, while preserving the largest.
Growers and observers have reported variable crop sets in many early and mid-blooming varieties, no doubt the result of the inclement weather experienced during the bloom. Later blooming types, such as the Butte and Padre, are presenting better crop potential, though it is still too early to definitively assess the crop.
Growers in all areas have been busy during the latter half of March, performing a myriad of activities. Fungicide applications in advance of the past week’s storms, both by ground and air, have been completed to protect the developing nutlets and leaves against infection. This is a critical time of year for fungal development. Clusters of jackets split by the developing nuts can be a prime source of infection if not cast from the tree. While no one wants to see winds strong enough to blow over trees, a bit of wind helps to scrub the jackets and aborted nuts out of the canopy and dry the foliage, thus reducing disease potential. Growers have also been applying fertilizers and mowing vegetation within the orchards. Excessive weed growth can allow temperatures within the orchards to drop to damaging levels on colder mornings, while a clean orchard floor absorbs heat from the sun and radiates it back out overnight.
Quite a few growers with orchards on sandy soils have reported problems with Bacterial Blast, caused by Pseudomonas syringae, an opportunistic bacterium which also causes Bacterial Canker and bud drop. The bacteria have caused bud mortality in a number of young orchards, significantly impacting the crop potential and causing growers experiencing the worst problems to question the future of the impacted orchards.
While the recent rainfall has been more than ample to meet the orchards moisture requirements, some growers have briefly run their irrigation systems, just long enough to apply liquid fertilizer materials, thus saving a pass with relatively heavy tractors and spreaders. Several local irrigation districts filled their network of canals over the past week. However, other than for spreading fertilizer, irrigations are not yet needed.