Agriculture Reference
In-Depth Information
adult moths to reproduce. The navel orange worm's progress through its
life stages, like that of most insects, is conditioned by environmental heat
units. There are three or four flights (generations) in a year. NOW do not
diapause (hibernate) during the winter and must have continual access to
food.
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The navel orange worm migrated to the Central Valley just as almonds
were being established as a commercial crop and as this crop's center of
production shifted from the coastal counties to the Sacramento Valley.
Initially almonds were dry-farmed, and the harvest labor requirements
constrained its expansion. Workers knocked almonds from the trees with
mallets and poles, passing through the orchard several times as varieties
ripened, swept the nuts onto tarps, and dragged them to the orchard
edges by horses. This was done in late summer, when all growers were
competing for labor.
In the 1950s, significant investment by the state of California in the
University of California's agricultural research and massive new water
projects revolutionized almond production. UC contributed a package of
improved production techniques. Mechanization reduced labor require-
ments by 75 percent. New, shorter tree varieties were more productive.
Chemical fertility and pest-management programs boosted yields. The
“shaker”—looking like an enclosed, low-hung go-kart—zips from tree
to tree, seizing the trunk with a huge mechanical arm and shaking the
nuts off. This device made it economically efficient to harvest an entire
orchard block at once. A mechanical sweeper follows, shaping a long,
continuous nut pile down the row middles. Finally, a loader scoops up
the nuts which conveys them to a semi-truck at the edge of the orchard
and transports them to the processor. The State Water Project brought
irrigation to hundreds of thousands of new acres in the southern San
Joaquin Valley, provoking a tremendous expansion of almond acreage.
With support from the Almond Board, the insecticides azinphosmethyl
and carbaryl were tested and registered for use on the navel orange
worm in 1976. In the market, almonds evolved from a rare treat to a spe-
cialty crop, and are now a common industrial input for snack foods.
Both humans and insects find them tasty.
Revolutionary practices have re-configured the geography and ecology
of almond production. California growers now produce 80 percent of
the global almond crop. Yields per acre climbed from an average of 213
