42 Forest Club Annual 



have at hand the daily records for the current season. To be of 

 the greatest value these should be taken in his immediate locality. 

 This usually entails entirely too much work to be considered 

 worth the trouble involved. 



A simpler way of making the same comparisons, therefore, 

 is to note the effect of these factors on the vegetation. The ad- 

 vance of the season, its earliness or lateness, the abundance or 

 lack of a certain factor such as temperature or rainfall, is defi- 

 nitely indicated in the behavior of plants. The most obvious 

 index is in the time of the leafing, flowering, fruiting, etc. This 

 method, in common with the more mechanical records, requires 

 the establishment of average dates. These can only be had by 

 securing records for many years. The average dates once estab- 

 lished, the annual occurrence of the different phenomena serving 

 as an index to that particular season is automatically recorded by 

 the plants and placed before us where all may see. 



Likewise, for a climate there may be complete meteorological 

 records, the extremes and averages of which serve as an accurate 

 index for comparisons with other climates. As a general index, 

 however, as for seasons, the meteorological records are sometimes 

 inadequate. They are not generally available, have to be inter- 

 preted in terms of climate when they are available, and require 

 similar records if a comparison is to be made. If, however, the 

 numerous types of vegetation were correlated with climate, the 

 presence of a type would then be a much more usable index than 

 the records of climatic factors and it would have the additional 

 advantage of being usable for comparative purposes where 

 meteorological records do not exist. For instance, if one was to 

 visit the interior of China and find a beech-maple forest it would 

 be safe to make the assumption that the climate of that region 

 is very similar to that of the region in America where the beech- 

 maple forest is found. 



There is an obvious need, therefore, of systematic and con- 

 tinuous records of the time of leafing, flowering, fruiting, and 

 leaf falling of the important conspicuous plants. Such plants 

 are the trees. They are perennial, more generally known than the 

 herbaceous plants and display widely varying habits. These are 

 known as phenological records, and those available in this coun- 

 try so far are extremely inadequate for anything but the very 

 broadest generalizations. In most cases their collection has been 

 sporadic. Only one case is known where records have been kept 

 for a long term of years. For many rather important species no 

 records whatever exist. For the more common species the records 

 are scattered and so lacking in uniformity that it is a difficult 



