Almond trees in the central San Joaquin Valley are responding well to growing conditions and little, if any, insect or diseases pressures so far this season, says agronomist Eli Akel.
Based at Fresno, Calif., his company, Akel AG Consulting, works with almond farmers in Fresno, Kings and Madera counties.
“Trees are looking good,” he says. “The majority had a good nut set and most growers have a better-than-average crop at this point. The cool weather has been good for nut sizing and has served to proliferate the trees toward next year’s bud development. Sampling the nuts, however, reveals a slight percentage of under-developed nuts. Now, we need warm temperatures to put the normal harvest date back on track.”
Until the first part of June, trees had escaped heat stress and moderate temperatures had prevented any mite problems. Also, earlier fears of an invasion of leaffooted plant bug have vanished.
“We survived the scare,” Akel says. “The wet spring weather produced a flush of vegetation outside of orchards. The insects remained in their overwintering habitat longer and didn’t fly into orchards before hardening of almond shells.”
Orchards had been pretty much free of fungal diseases this spring, until the first of June. Then, three days of rain, with precipitation amounts ranging from about one-half to two inches in his area, lead to a sporadic flare up of shot hole. A threat when there is frequent and prolonged spring rainfall, an early-season epidemic of shot hole may lead to heavy shedding of leaves and fruit drop.
Unusually strong winds last month caused problems in some orchards. “It’s not unusual to get winds of up to about 30 miles per hour at this time of year,” Akel says. “But in May, they were so intense in some areas that they knocked down some almond trees. In rank trees, like Padre, the winds knocked nuts down and tore off twigs, leaving only sticks showing.”
In some cases, trees succumbed to a combination of wet soils and high winds. “Some trees with a heavy top crop load weren’t being maintained with proper pruning practices,” he says. “That caused the center of gravity of rank trees to shift and they toppled under the force of the winds and excess soil moisture.”
The unseasonably cool spring has delayed nut development. “Normally, by early June, we would have seen uniform nut hardening,” Akel says. “We began seeing some of that at the start of the month, but the nuts are about a week to 10 days later than normal.”