136 



JOURNAL OF FORESTRY 



within one or two feet of the height to which they are killed in the 

 more closely spaced stand ; the loss of trees through suppression has 

 been less than a third as great. So far, the stand with wider spacing 

 has failed to equal the basal area of the other, but this difference will 

 probably continue to grow smaller rather more rapidly than it has in 

 the past, though, during the past four years, the stand with 4J/^-foot 

 spacing has gained only two square feet over the other. The race 

 between them from now on will be an interesting thing to watch. 



In view of the fact that these stands are growing south of the 

 natural range of white pine in this part of the state, it was to be 

 expected that their development would fall below that of those found 

 well within its original habitat. However, a comparison with the yield 

 table for Quality I white pine in New Hampshire, given on page 21 of 

 the bulletin, "White Pine Under Forest Management," by E. H. Froth- 

 ingham. shows that such has not been the case, especially with the -IJ^- 

 foot spacing. If values for the age of 17 years are computed by inter- 

 polation from Frothingham's figures, they run as follows: 



Average height. . . . 

 Average diameter. . 

 Basal area per acre 

 No. trees per acre. 



[anipstiire stand 



18.5 feet 



.3.34 inches 



86.8 square feet 

 1.441 



Michigan stand 



21.8 feet 



3.3 inches 



118.7 square feet 

 1,945 



The figures for average height are not exactly comparable, since 

 those for New Hampshire are the average for dominant trees only, 

 while those for Michigan are for all the trees in the stand. The 

 character of the soil in this case makes these results even more sur- 

 prising, since it is composed largely of sand and had been badly worn 

 out by a long period of wasteful agricultural use. Its one virtue lies 

 in its generous depth. 



In all cases up to the present stage of development, the conifers 

 planted, intolerant as well as tolerant, have demonstrated their ability 

 to produce and maintain good forest conditions in pure stands. Ground 

 cover of all sorts disappeared as soon as the stands became closed, 

 and a good forest floor has been formed. These conifers include the 

 Scotch, white, Austrian, and western yellow pines, Douglas fir ( Rocky 

 Mountain form), and Norway spruce. (All attempts to grow srock 

 from Pacific Coast seed of Douglas fir have failed becm-e of winter 

 killin?. even in winters that are rnusuallv mild for thi> locality. ) 



