TIMBEK GEOWIXG AND LOGGING PRACTICE IX CALIFORNIA 53 
At present no tree-killing diseases are known to exist in the Cali- 
fornia pine region which can be directly controlled under prevailing 
economic conditions. In time the sugar pine may be attacked by the 
white pine blister rust, which is already present in the pines of the 
^sTorthwest. If that transpires, organized effort, similar to that 
recommended for combating insects, will become necessary. The 
methods of control are being worked out by the forest pathologists 
of the Bureau of Plant Industry, United States Department of 
Agriculture. 
THE RETURNS TO THE LANDOWNER 
The forests obtained under the simple measures outlined above 
will not, in most cases, fuU}^ utilize the productive power of the land, 
for the design is primarily and above all to prevent forest destruc- 
tion. With minor exceptions, however, forest lands so cut over 
and so protected will continue to produce commercial stands of 
timber, and lumbering operations so restricted will cease to create 
new brush fields or stands so seriously understocked as to be unmer- 
chantable. The owner of the land will possess an asset rather than 
a liability. 
The volume of wood produced will depend on the quality of the 
land as well as on the treatment of the forest. On good sites, a 
growth of 400 board feet an acre yearly may be expected, where 
young trees were abundant before logging. The rate will be lower 
on poor sites, though generally not less than 75 to 100 board feet. 
Part of this growth will take place on trees reserved under the diame- 
ter limit cutting as well as the occasional larger seed trees, but from 
two-thirds to three- fourths will be on the saplings and poles from 4 
to 12 inches in diameter at the time of cutting. Thus a light second 
cut within 30 to 50 years will be possible on most lands, the excep- 
tions being poor sites with scanty advance reproduction. 
SUMMARY OF ESSENTIAL MEASURES 
A restatement of the essential physical steps for keeping forest 
lands productive must include the following provisions: 
SLASH DISPOSAL AND PROTECTION 
Advance reproduction should be protected from fire before, during, 
and after logging. This can be accomplished by systematic pro- 
tection of the virgin forest, no broadcast burning of the forest, care 
with and control of fire during logging, no broadcast burning of slash 
after logging, partial disposal of slash, and systematic patrol of 
cuttings for 8 to 12 years after logging. 
LOGGING METHODS 
Logging methods should not be such as to destroy advance repro- 
duction more than absolutely necessary. Horse logging should be 
used on ground adapted to that type of logging, unless caterpillar 
logging proves as good or better both from cost and damage stand- 
points. High-lead yarding and the use of high-speed machines 
should be discontinued; ground or modified lead with low-speed 
machines leave the land productive. 
