170 BULLETIN 1059, U. S. DEPARTMENT OF AGRICULTURE. 



EXTERNAL FIELD OBSERVATIONS. 



At each station where the environment is being studied, one or 

 more individual trees should be permanently marked and numbered, 

 and their condition should be a matter of daily observation. The 

 number of trees chosen will depend upon the composition of the 

 stand. Where even-aged stands of one species are studied, probably 

 two representative ■ trees of the dominant and codominant classes 

 will be sufficient. In all-aged stands, at least three trees of various 

 ages above reproduction should be included and two sets of such 

 trees if the stand contains more than one prominent species, or if the 

 site is being studied from the standpoint of more than one species. 

 In studies of reproduction conditions, the smallest seedlings available 

 should be under observation. 



In these external observations, Forest Service Form 416 may be 

 used as a guide, since it covers comprehensively the ordinary phe- 

 nological observations. A reduced copy of this form may wellbe 

 kept in the field notebook, and the field observations may be given 

 in the form of numbers corresponding to the captions of the " Phe- 

 nological Observations " form. For example, " 1 " would be used to 

 indicate that buds were beginning to swell. 



As has been said, ocular observations on these common phenomena 

 of growth, especially at the actual beginning of tree growth in the 

 spring and its termination in the fall, are too crude. Some method 

 of measuring and recording the actual growth from day to day is 

 required. A number of auxometers might be mentioned, but a meter 

 really adapted to plants in the field, and especially the exposed sway- 

 ing tops of trees, has not been produced, so far as the writers know. 

 There is unlimited field here for invention. 



Form 416. 



[U. S. Department of Agriculture, Forest Service.] 



PHENOLOGICAL OBSERVATIONS. 



Species 



Period covered by observations 



Name of observer 



Residence , ] 



(State.) (County.) (Town, i 



General character of country. — Mountains; foothills; plains; river valley; 



seacoast. 

 Situation of trees. — Level; slope (north, cast, west, south); hilltop; river bot- 

 tom; soil (sandy, clayey, heavy, light, deep, shallow, moist, dry) ; forest; 

 open ground; park; street. 



(Please check the words which apply to your particular locality and to the trees 

 observed.) 



Approximate elevation above sea level 



Location of nearest Weather Bureau station 



State if season was wet or dry, early or late, etc 



