RESEARCH METHODS IX STUDY OE FOREST ENVIRONMENT. 171 
Date. Date. 
1. Swelling of buds 9. End of leaf falling 
2. Bursting of buds 10. Beginning of seed ripening 
3. Beginning of leafing out 11. General seed ripening 
4. General leafing out— 12. Beginning of seed falling 
5. Beginning of blossoming 13. End of seed falling 
F. ^General blossoming _ 14. Quantity of seed 
7. Change in eolor of foliage 15. Quality of seed 
S. Beginning of leaf falling 
General remarks -, 
Instructions on back of this form should be followed strictly. 
Under the name ; * dendograph " McDougal 22 . lias designed a new 
Instrument for measuring and recording the diameter growth of tree 
stems. This instrument is being thoroughly tried out. It will 
probably be a vary valuable adjunct. It is not simple in construction 
or operation, however, and will always be too expensive to be exten- 
sively used. It would seem that a beginning must be made in a more 
simple way. perhaps through circumferential measurements, even 
though a number of complicating factors must be taken into account, 
such as the expansion of the tree and of the tape with increased tem- 
peratures. 
INTERNAL OR PHYSIOLOGICAL OBSERVATIONS. 
Although the forester is prone to think of growth as the major 
reaction of interest, it is entirely possible that there may be positive 
gain in studying the more fundamental reactions which lead up to 
g'rowth. For example, in the conifers, the outward evidences of 
growth may disappear by midsummer, so far as height accretion is 
concerned; yet diameter growth continues longer, and this period 
of relative inactivity is of great importance in accumulating a reserve 
for the effort of the following season. Is it not logical, therefore. 
that the growing season for trees should be considered to be the 
entire period in which materials for growth are being produced ? 
Again, while growth is a large factor when competition begins, 
the critical conditions which have the greatest bearing on the success 
of the individual and species, and thereby affect most acutely the 
character of the plant formation, may, in the case of all perennial 
plants, be encountered not in the growing season but in the dead of 
winter. Through neglect of this period erroneous conclusions may 
again be reached as to the importance of various conditions in 
building up the plant formation. 
It should therefore be most desirable to be able to determine the 
physiological conditions of the plant frequently in order that its 
reaction to every change in environment may be followed. The 
»MacDougal, D. T. Growth in Trees. Pub. 307, Carnegie Inst. Washington. 1921. 
