Acorns from different trees.]

=11.= =Quercus palústris= Du Roi. Pin Oak. Plate 50. Medium to large

trees with very tight bark, the furrows shallow and generally wide;

twigs at first pubescent, soon becoming smooth and reddish-brown; leaves

on petioles generally 1-5 cm. long, blades about 7-15 cm. long, usually

about 2/3 as wide, sometimes as wide as long, ovate to obovate in

outline, narrowed to broadly truncate at the base, the margins divided

into 5-7 lobes by deep and wide sinuses, except leaves that grow in the

shade, the sinus cuts the blade to more than half way to the midrib, the

lobes are widest at the base, or sometimes widest near the apex, the

lobes usually somewhat toothed or lobed and end in 1-7 bristle tips,

leaves hairy when they first appear, soon becoming glabrate and a glossy

dark green above, a paler green beneath and smooth except tufts of hairs

in the axils of the principal veins; acorns sessile or nearly so, single

or in clusters; nuts subglobose or ovoid, generally 10-12 mm. long, the

ovoid form somewhat smaller, covered about 1/4 their length by the

shallow cups; cups saucer-shape and generally flat on the bottom, those

with the ovoid nuts are rounded on the bottom; scales pubescent on the

back, and rounded or blunt at the apex.

=Distribution.=--Massachusetts, southwestern Ontario, Michigan to Iowa

and south to Virginia and west to Oklahoma. Found in every county of

Indiana. It is found only in wet situations where it is a frequent to a

common tree. It prefers a hard compact clay soil with little drainage

hence is rarely met with on the low borders of lakes where the soil is

principally organic matter.

=Remarks.=--Wood similar to red oak, but much inferior to it. It is

tardy in the natural pruning of its lower branches, and when the dead

branches break off they usually do so at some distance from the trunk.

The stumps of the dead branches which penetrate to the center of the

tree have given it the name of pin oak. It is also sometimes called

water oak, and swamp oak.

For street and ornamental planting it is one of the most desirable oaks

to use. It is adapted to a moist soil, grows rapidly, and produces a

dense shade. When grown in the open it develops a pyramidal crown.

The nut of this species always has a depressed form, except a tree or

two in Wells County which produce ovate nuts which are cone-pointed, and

in bulk about half the size of the ordinary form. This form should be

looked for to ascertain its area of distribution.

[Illustration: Plate 50.

Trees of Indiana First Revised Edition (Publication No. 13, Department of Conservation, State of Indiana) · 第 99 / 265 题