sept-oct-2020

IN YOUR ORCHARD herbicides may cause significant tree damage under these conditions, particularly on low organic matter soils, and applicators should be particularly careful when spraying those products. Remind operators to shut off the booms before slowing down at the end of the row and, when starting down a row, to not to turn on the booms before reaching the speed used when calibrating the sprayer. Pollination Good pollination is critical in every year, with strong hives (eight frames of bees or better per hive) delivering significantly better pollinization than weaker ones. Late fall is a good time to sign a pollination contract (including hive strength language) to lock in that key service ahead of bloom. Waiting for a “deal” for bees might leave you without good pollination in the field next bloom. Consider planting a bee pasture this fall to feed bees next spring. Pruning Trees Pruning/roping young trees is important to good tree structure and future production. Without careful early pruning and (where needed) roping there is a significant risk of limb breakage through wind torque and/or crop weight. Select a limited number of scaffolds, three to four, up and down the trunk and as evenly distributed around the trunk as possible. If multiple scaffolds, five to six, are selected, they must be well spaced up, down and around the tree or there is a good chance you will have a heartbreaking, days-long appointment with a chainsaw and a buck-rake in a couple of years. There is no cost savings in skimping on pruning scaffold selection. Pruning potted trees planted this year can be particularly challenging. If trees were not pruned at planting and go into winter with a mess of scaffolds near or at the top of the trunk, even with good shoot and trunk growth, consider cutting off all scaffolds and letting the tree push new scaffolds up and down the trunk next spring. There is an excellent chance that you will be happier with the results (better orchard structure for the life of the orchard) than trying to cope with the mess resulting from not starting over. Time pruning and apply fungicide to protect pruning wounds as young trees are particularly vulnerable to pruning wound infection by canker diseases. Recent research in Dr. Florent Trouillas’ lab (UC Extension Specialist) has provided answers to the questions: “When do I prune ? ” and “When are pruning wounds most vulnerable ? ” Pruning in December resulted in less canker disease infection than in the fall. Pruning wounds were most vulnerable to infection right after cutting. Infection susceptibility decreased by 60 percent at two weeks after pruning and 75 percent after three weeks from pruning. In field trials, Topsin-M provided the best pruning wound protection (82 percent infection reduction). Rain is needed to carry disease spores and allow infection, so cuts should be sprayed ahead of any forecasted rain. Nematode Sampling Don’t push out an old orchard that you plan to replant anytime soon without first taking a nematode sample. Sample soil and small roots from 4 to 24 inches with a soil probe or auger from different locations across a field. Separate samples should be taken from different soil types across a field. Keep the samples cool and submit to a lab to conduct the analysis as soon as possible. Take a Walk Walk through your orchard to check general appearance of the trees and soil and ask yourself some important questions. Is early leaf drop more pronounced in one area compared to another ? How does shoot growth from 2020 season compare across the block ? Is there ponding in certain areas right or during after irrigation ? Encourage your PCA/CCA and key employees to do the same and compare notes. This information helps direct work to improve tree performance in certain areas of the orchard, which should improve the bottom line for the whole planting. Best wishes for a productive and restful fall. 4 0 A L M O N D F A C T S