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white oak group for cultivation in this country, though in special 
places where the atmosphere is moderately humid, and the ground 
good and moist ; the “ white oak,” Q. alba, L., and the “swamp white 
oak.” Q. bicolor, Willd., may prove a success. The burr oak grows 
to a large size in Central N. America, its average height bein 
from 80 to 90 feet, with a diameter of 3 to 4 feet, though under very 
favourable conditions specimens have been noted up to 170 feet in 
height, with adiameter of from 6to7 feet. “Forest Planting Leaflet,” 
Circular 56, U.S. Dept. of Agriculture, deals with this species, and 
from it the following notes have been extracted. “ The burr oak is 
one of the most valuable hardwood trees in North America, The 
wood is heavy, hard, very strong and durable. In the markets it is 
not, and need not be, distinguished from white oak, and it is used 
for the same purposes. The heartwood makes especially good fence 
posts and railroad ties, but the sapwood does not last long in the 
ground, It is best suited to deep, rich, river-bottom soils. It will 
maintain itself in poorer upland localities, but it is recommended for 
planting only where the soil is fairly good, moist, and well-drained, 
and where protracted droughts are infrequent. It is rather in- 
tolerant of shade, and will not thrive beneath the crowns of taller 
great strength is required, and not to last so long in the ground, 
but to work easier and to be often preferred for interior finish and 
for cabinet work. As a rule it is considered to be better than other 
U.S. Dept. of Agriculture.) In the sandy soil of Kew it makes 
satisfactory progress. When grown in the open the head is 
girth at 5 feet from the ground 
