1866 ARBORETUM AND FRUTICETUM. PART LUI. 
abundant; and sometimes not above a handful of 
acorns can be found in a large forest. The acorns 
have a very thin and brittle shell: they ripen 
early, and, according to Cobbett, germinate so 
easily, that, “ if warm rains come on in the month 
of November, which they very frequently do in 
America, the acorns still clinging to the trees 
actually begin to sprout before they are shaken 
down by the winds.” (Woodlands, § 542.) Some 
trees produce acorns of a deep blue colour; but 
_ Michaux had seen only two specimens of this _ 
variety; one in the grounds of Mr. Hamilton, >= 
near Philadelphia, and the other in Virginia. The 
bark of this tree is white (whence the species de- 
rives its name); and, though it is often variegated 
with large black spots, it has such a silvery hue, 
that the tree may be easily distinguished by it 1726 
even in winter. The bark is scaly; and, on young 
trees, it appears divided into squares, but, on old trees, into plates laterally 
attached. The wood is reddish, somewhat resembling that of the British oak, 
but lighter, and less compact. The rate of growth of this tree, in British gar- 
dens, where the soil is good and the situation sheltered, may be considered as 
nearly equal to that of the common oak; but without shelter, even in a good 
soil, the tree has a stunted appearance for many years, as is evident from a 
tree of 20 years’ growth in the Hackney arboretum, and several in the Horticul- 
tural Society’s Garden, of two of which fig. 1727. presents portraits. The largest 
1727 
a ~ 42320 ees 
trees that we know of are between 60 ft. and 70 ft. high; and, both at York 
House near Twickenham, and at Muswell Hill, they have ripened acorns. 
Geography. Q. alba is found as far north as Canada, N. L. 46° 30%; and 
thence it was traced by the two Michaux, as far as Cape Canaveral, N. L. 28° ; 
and westward, from the ocean to the country of Illinois; a distance of above 
1200 miles from north to south, and nearly as much from east to west. It 
is not, however, equally distributed over this extensive tract of country, being 
found either in very dry and sandy, or in very rich, soils. The white oak is 
in the greatest abundance in those parts of Pennsylvania and Virginia that lie 
