42 The New York State College of Forestry 
TABLE XIII 
YELLow Bircu, HEIGHT, DIAMETER, AND VOLUME GROWTH, LAKE OZONTIA, 
FRANKLIN County, N. Y., 1919 
AGE | Total height D. B.H. Dial 
ecubie feet 
TON: 5 okgevers eters otters f 3.8 TAS 0.14 
Pe ee A, Sc 28.1 2.9 0.64 
Oe ee ote ener eaetoene ees 38.4 4.3 1.96 
AOs ti Sos ree een 44.6 sev 2.52 
Ot rseta sve beter ee te 49. 5.9 SA hs) 
GONE we arnnieutapietek 53.6 6.5 4.66 
A study of birch growing under shade of adjoiming hard- 
woods shows at sixty years of age about 50 per cent of the 
height and diameter development found in the trees of the same 
age grown in the open. 
Height growth studies made on 170 spruce trees grown under 
shade of yellow birch at Lake Ozonia shows an annual height 
growth of about two-tenths of a foot. While this is relatively 
slow, it is faster than that of spruce under mixed hardwoods. 
Stands of this type can be profitably thinned to allow increased 
growth of the spruce understory. 
birch, second growth — St. Lawrence County: 
A second area of pole stand of yellow birch and aspen was 
found in southeast St. Lawrence county, and data are submitted 
to show the result of slightly different conditions. This area of 
some twenty-five acres is found on spruce flat type, and was 
burned about forty years ago, followed by reproduction and a 
light ground fire about ten years ago on part of the area. Strips 
and sample plots were run on twenty-three acres of the area, 
and the results shown in four tables (14, 15,16 and 17). The 
effect of the second ground fire was to kill a number of the 
smaller birch, hasten the destruction of the aspen, thin the 
crown of the stand, and allow considerable reproduction of in- 
tolerant species. The amount of soft wood reproduction was 
doubtless reduced in number. It can be readily seen that the 
aspen is decadent, and was once the dominant tree on the area. 
A third area was studied and results found comparable to 
the preceding two, which makes it obvious that small burns sur- 
