New Work in Forestry and Uses of Wood

One example of progress in forest research is the discovery that hybrid vigor applies to trees in much the same way as it does to animals and field crops such as corn and wheat. The pine trees shown above are all 3 years old and were grown in the same seedbed under identical conditions. At left is an average seedling of Western white pine; at right an average Eastern white pine. The two in the middle are typical of seedlings that result from crossing Western and Eastern pines. The young tree shown at the left, below, is a Jeffrey pine; at the right is a Coulter pine. The one in the center is a back-cross hybrid of the two. All three, under test at the Institute of Forest Genetics, Placerville, Calif., are 4 years old.

Of the various different factors that are known to be forest-fire hazards, wind velocity, the amount of moisture in forest fuels, and the condition of vegetation are the most important. Improved scientific methods are used to prevent destruction of our forests by fire. Above, left, are several devices that measure fire danger: Anemometer on top of shelter box; moisture-indicator sticks in foreground; scales shelter, for measuring moisture in the sticks and a rain gage at right. A standard alidade is used by Forest Guard Guy let to determine and report exact location fire.