current investigations in controlled
environments.
Under field conditions it is impossible
to control all environmental factors which
affect plant growth. Years may pass before
all of the various climatic factors
which influence plant growth and behavior
would occur naturally. Extensive
experiments would have to be conducted
year after year under conditions of varying
climate, soil fertility, moisture status:
plant development and a host of other
variables in the hope that eventually 'a
sufficient amount of information may be
collected, which when treated statistid
cally, will bring to light the critical factors
relating climate to growth. However,
upon the completion of the Earhart Plant
Research Laboratory at the California
Institute of Technology in Pasadena, it
became possible, for the first time, to perform
experiments continuously throuphout
the year and to preselect and control