LAWS OF TALL-TREE GROWTH 535 



and gives the numbers for the species mentioned by which to multiply 

 the cube root of the square of the stump-radius (in inches) to obtain the 

 greatest height, H (in feet), to which the tree could rise in still air on 

 that radius. 



Species E 



Douglas fir 1,580,000 



Western red cedar 950,000 



Norway pine 1,380,000 



Longleaf pine 1,620,000 



Shortleaf pine 1,400,000 



Redwood 1,060,000 



Wliite pine 1,070,000 



Cypress 1,220,000 



Western yellow pine 980,000 



White oak 1,250,000 



It is interesting to note, in connection with this table, that the low 

 value of w for cedars gives Douglas firs and cedars the same number in 

 the last column, and while the Pacific Coast Douglas fir is the most 

 remarkable of all .\merican trees for height, the cedar is near the bottom 

 of the list. The cedar never rises above about one-fourth its still-air 

 possible height, while the Coast Douglas fir at 50 years of age is a third 

 of its still-air height, and this ratio it steadily increases for a long period, 

 being at 110 years old four-tenths its possible height and at 180 years 

 forty-four hundredths of its possible height, holding this ratio steadily 

 for the next 100 years, and at 300 years of age it is still over forty-three 

 hundredths of its possible height. The tallest Douglas fir yet measured, 

 330 feet high, diameter 71 .6 inches, is fifty-t^o hundredths of its great- 

 est possible still-air height (see (F) following). The difference in 

 height, on the same stimip-radius, between cedars and Douglas firs must 

 be attributed to difference in energy of the terminal bud. 



It will be observed in (D) that Tennessee white oaks, California 

 yellow pines, Louisiana cypress, Michigan and Pennsylvania white 

 pines have the same coefficient for H. This means for these trees 

 practical equality of terminal bud energy, and that their heights on the 

 same stump-radius are about as their nimibers in the last colimin above, 

 namely, 53.1, 55.5, 56.8, 59.4. 



(F) The following table gives the diameters and the height of the 

 tallest trees actually measured in the United States Forest Service 

 Ivmibering operations. The figtu-es for bigtrees were given by Mr. 

 Woodbury^ Assistant District Forester at San Francisco, those for 

 Oregon yellow pines and Oregon Coast Douglas firs by Mr. Ames 



