he rows of coffee trees, both as a means of
obtaining additional revenue and to shade the young coffee plants. Corn,
beans, cotton, peanuts, and similar plants are most generally used.

PESTS AND DISEASES. The coffee tree, its wood, foliage, and fruit, have
their enemies, chief among which are insects, fungi, rodents (the
"coffee rat"), birds, squirrels, and--according to Rossignon--elephants,
buffalo, and native cattle, which have a special liking for the tender
leaves of the coffee plant. Insects and fungi are the most bothersome
pests on most plantations. Among the insects, the several varieties of
borers are the principal foes, boring into the wood of the trunk and
branches to lay _larvae_ which sap the life from the tree. There are
scale insects whose excretion forms a black mold on the leaves and
affects the nutrition by cutting off the sunlight. Numerous kinds of
beetles, caterpillars, grasshoppers, and crickets attack the coffee-tree
leaves, the so-called "leaf-miner" being especially troublesome. The
Mediterranean fruit fly deposits _larvae_ which destroy or lessen the
worth of the coffee berry by tunneling within and eating the contents of
the parchment. The coffee-berry beetle and its grub also live within the
coffee berry.

Among the most destructive fungoid diseases is the so-called Ceylon leaf
disease, which is caused by the _Hemileia vastatrix_, a fungus related
to the wheat rust. It was this disease which ruined the coffee industry
in Ceylon, where it first appeared in 1869, and since has been found in
other coffee-producing regions of Asia and Africa. America has a similar
disease, caused by the _Sphaerostilbe flavida_, that is equally
destructive if not vigilantly guarded against. (See chapters XV and
XVI.)

The coffee-tree roots also are subject to attack. There is the root
disease, prevalent in all countries, and for which no cause has yet been
definitely assigned, although it has been determined that it is of a
fungoid nature. Brazil, and some other American coffee-producing
countries, have a serious disease caused by the eelworm, and for that
reason called the eelworm disease.

Coffee planters combat pests and diseases principally with sprays, as in
other lines of advanced arboriculture. It is a constant battle,
especially on the large commercial plantations, and constitutes a large
item on the expense sheet.

_Cultivation by Countries_

Coffee-cultivation methods vary somewhat in detail i