170 JOURNAL OF FORESTRY 



Trees bearing heavily were located by diligently tramping the roads 

 and trails of a great part of the Puget Sound country. In all, it is 

 probable that fifty days were spent in this manner. Some time was 

 also spent examining hemlock trees which had been felled in logging 

 operations. If a tree were found which was bearing heavily, unless 

 too large, it was given a thorough examination. Generally the tree 

 was climbed. The trunk and limbs were examined carefully for in- 

 juries; twigs were examined to determine past seed years,* and in 

 some cases even the roots of the trees were examined. Thus small 

 trees were examined literally from top to bottom. Points particularly 

 noted were : The site, the rate of growth, the treatment to which the en- 

 vironment had been subjected (through logging, fire, etc.), the amount 

 of seed produced, evidences of past seed years, injuries to the tree 

 (such as fire, insects, fungi, mechanical bruises, etc.), and the general 

 health and position of the tree in the crown cover. About 300 trees 

 were examined in greater or less detail. Most of these trees either 

 bore heavy crops of cones on the tree as a whole or on some individual 

 limb in particular. Other trees were examined for a number of rea- 

 sons, generally as checks and for comparison. Most of the trees ex- 

 amined either had been attacked by insects or fungi, scorched by fire, 

 suffered from mechanical injuries, such as decapitation, tnmk and 

 limb abrasions, partial windfall, or had been left after logging and had 

 been subjected to the lowering of site conditions due to drying out of 

 the soil and loss of humus. 



It is of interest to note that on a study of this kind it is practically 

 impossible to tabulate the data obtained in order that one unfamiliar 

 with the work might judge of the correctness of the conclusions 

 reached. The reason for this may be as follows : An attempt is made 

 to establish a fact. In this case it is whether or not hemlock trees are 

 stimulated to seed production by external factors. Even though the 

 fact be well established as a generality, yet the response of the tree to 

 various stimuli may vary greatly in intensity under different circum- 

 stances. These circumstances particularly are the intensity of the 

 stimulating factor and the size, age, and health of the tree prior to 

 becoming affected. A very large, healthy, tree affected with a maxi- 

 mum stimulation will respond very differently than one which was in 

 poor health prior to stimulation. There are, moreover, a half dozen 



^This was done by the location of the cone scar in reference to the annual 

 growths. It was found possible to determine whether or not a twig had borne 

 any cones during the past six years. Determinations were much more difficult 

 on young twigs than on old, slowly growing sprays. 



