_Gophers._—These often do great damage to the trees by girdling them
just below the surface of the ground, or if they do not actually girdle
the trees, they cut them enough to devitalize them and, in addition, the
wounds made by their gnawings frequently become infected with crown-gall
organisms. The only safe means of control is the constant use of traps
supplemented by poisoned bait.
_Squirrels._—Squirrels are very troublesome, as they harvest a large
amount of almonds before they are sufficiently ripe to be harvested by
the grower. The use of poisoned grain or “gas,” if used over a large area
of surrounding territory, will prevent serious depredations.
_Birds._—Birds also carry off large amounts of almonds if the orchards
are near open country or hills, especially if wooded. Crows, bluejays,
blackbirds, yellow-hammers, robins and other similar birds are the worst
offenders. Sometimes linnets eat off large numbers of fruit buds in the
spring in a few of the newer sections where plantings are scattered.
Sap-suckers have been known to girdle entire trees or large branches by
cutting large numbers of holes in a series of lines close together around
the trunk or limbs.
_Morning-glory._—This is probably the worst of the weeds in almond
orchards, and is the hardest to control. Sheep and chickens may be used
with excellent results, provided care is taken to see that the sheep are
not allowed to go hungry, for then they will bark the trunks of the trees
very quickly. An excellent plan is to arrange gates so that the sheep
must go through the orchard from pasture to get water. In passing back
and forth they will forage over the entire orchard and dig up all the
morning-glory in sight. Chickens are fond of the succulent new shoots,
and will keep them below the ground until the underground stems and roots
weaken and die. Cultivation throughout the growing season, often enough
to prevent the morning-glory from developing any leaves for a whole year
at least, and longer if necessary, will starve the plants to death.