RESEARCH METHODS IN STUDY OF FORES*T ENVIRONMENT. 25 



Annual Summary. 



The annual summary of air temperatures on the " Summary " form 

 should be a tabulation by decades and months of the means or totals 

 obtained from the " Air Temperature Record," with the annual mean 

 or total, as the case may be, computed therefrom. Usually a separate 

 " Summary " form will be used for each datum to be summarized. 



In addition, as a part of the annual summary, there should be 

 worked out the mean or total for each datum for the growing season. 

 The limits of the latter may be determined, as indicated by the dis- 

 cussion in earlier paragraphs. 5 Whatever the criterion as to the 

 actual length of the growing season, it should be considered to begin 

 and end with even decades, and all means computed for the growing 

 season should be the sum of the decade means divided by the number 

 of decades. 



Form 10. 



Type 



[U. S. Forest Service, Physical Survey.] 

 SUMMARY. 



; station No. ; datum 



height or depth 



Year, t Dec- 

 ade. 













Month. 













Mean 

 annual. 



Jan. 



Feb. 



Mar. 



Apr. 



May. 



June. 



July. 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 





























Mean 

 grow- 

 ing 

 sea- 

 son. 



[Determined by comparing annual means for 1 foot and 4 feet.l 



Instruments. 



Approximate 

 Thermometers and shelters: range of prices. 



Mercurial thermometer (Weather Bureau pattern) $1.25 to .$3.00 



.Maximum thermometer (Weather Bureau pattern) 2.50 to 5.00 



Minimum thermometer (Weather Bureau pattern) 1.50 to 3.00 



Maximum and minimum thermometers are often sup- 

 plied in pairs. 



Support for maximum and minimum thermometers 2.00 to 2.50 



J i j - f i ■ n n i ( ■ r 1 1 shelter, complete, without supports 20.00 to 30.00 



matter of fad ti <■ temperature conditions tbat delimit the growth of plants, and 

 miferous trees are not known, and to attrmpt to fix a rule for determln 

 ins when the growing season begins and ends would, al tills stage, be extremely ar- 

 bitrary. 



