Homoptera present the usual problems to orchardists and gardeners
but are controlled by a variety of sprays.
Wild bees are plentiful, and there are a great variety of ants,
beetles, and butterflies. The Rocky Mountain tent caterpillar is a dan-
gerous pest in the forests, where it attacks and defoliates at least twenty-
four varieties of trees and shrubs; one species even attacks the evergreens.
A project of the Work Projects Administration has spent considerable
time in Santa Fe searching for insect enemies of these pests (which
have become alarmingly destructive in the mountainous sections) in
order to utilize nature's means of combating them.
Although its land area ranks fourth in extent among the forty-eight
States, New Mexico has a water area of only 131 square miles, the
smallest of any State in the Union. The conservation of the State's
water resources is therefore a matter of the utmost urgency, particu-
larly since the land is largely composed of vast arid and semiarid dis-
tricts which require irrigation for abundant productivity. Water is
thus more important to the State's present and future welfare than all
the coal or gold or minerals within its borders.
About 350 square miles of New Mexico's area may be regarded as
a vast plateau region, averaging 5,000 in elevation, intersected by nu-
merous streams forming narrow valleys and deep gorges. The south-
ern portion of the State is characterized by great stretches of plains, cut
by muddy rivers, split by occasional north-south mountain ranges, and
embracing fertile agricultural sections, all of which require irrigation.
Crops adapted to unirrigated districts are comparatively few in
number; hence the great emphasis placed upon irrigation. In the irri-
gated valleys, where the moisture factor is largely under control, practi-
cally all crops of the Temperate Zones can be raised successfully. Some
dry farming, or farming dependent entirely upon rainfall, is carried
on in the higher altitudes in the Estancia Valley and above the north-
east tier of counties, with periodic loss of crops due to drought. Plant
adaptation has probably received the least attention among conserva-
Irrigation in New Mexico, practiced by aboriginal Indian tribes in
prehistoric times, is the oldest in America, yet the problems attendant
upon modern irrigation are far more complex than the simple diversion
of water from streams into the fields. Any extensive reclamation
scheme requires intelligent and farseeing planning, involving the ex-
penditure of millions of dollars for dams, canals, and subsidiary works
for the control of flood waters, erosion, silt, and drainage. In New
Mexico, especially, the menace of silt carried by the rivers and streams