Michigan Trees Part 28

+Black Jack+

_Quercus marilandica Muench._

HABIT.--A small, shrubby tree 20-30 feet high, with a trunk diameter of 6-14 inches; spreading, often contorted branches form a rounded or obovoid crown.

LEAVES.--Alternate, simple, 5-7 inches long and broad; broad-obovate; more or less 3-lobed at the apex, the lobes entire or toothed, bristle-tipped, very variable in size and shape; thick and leathery; very l.u.s.trous and dark green above, yellowish and scurfy-p.u.b.escent beneath; petioles short, stout.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender, h.o.a.ry catkins 2-4 inches long; the pistillate rusty-tomentose, on short, rusty-tomentose peduncles; calyx 4-5-lobed, thin, scarious, tinged with red, pale-p.u.b.escent; corolla 0; stamens 4, with apiculate, red anthers; stigmas recurved, dark red.

FRUIT.--Autumn of second season; short-stalked acorns; cup turbinate, with large, red-brown, rusty-tomentose scales, inclosing about one-half of the nut; nut subglobose, about 3/4 inch long, yellow-brown, p.u.b.erulous; kernel yellowish.

WINTER-BUDS.--Terminal bud 1/4 inch long, ovoid, acute, prominently angled; scales light red-brown, rusty-hairy.

BARK.--Twigs at first light red and scurfy, later glabrous, red-brown, and finally brown or ashy gray; thick and almost black on the trunk, divided into nearly square plates.

WOOD.--Heavy, hard, strong, dark brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Southern Michigan (Ann Arbor and Lansing).

HABITAT.--Dry, sandy or clay barrens.

NOTES.--Rare in Michigan.

[Ill.u.s.tration: +Shingle Oak+

1. Winter twig, 2.

2. Portion of twig, enlarged.

3. Leaf, 1/2.

4. Flowering branchlet, 1/2.

5. Staminate flower, enlarged.

6. Pistillate flower, enlarged.

7. Fruit, 1.]

+f.a.gACEAE+

+Shingle Oak+

_Quercus imbricaria Michx._

HABIT.--A tree 40-50 feet high, with a trunk diameter of 1-2 feet; forming a rather open, rounded crown of slender, horizontal branches.

LEAVES.--Alternate, simple, 4-6 inches long, 1-2 inches broad; oblong-lanceolate to oblong-obovate; entire or somewhat undulate; thin, very l.u.s.trous, dark green above, paler and p.u.b.escent beneath; petioles stout, p.u.b.escent, 1/2 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender, h.o.a.ry-tomentose catkins 2-3 inches long; the pistillate on slender, tomentose peduncles; calyx 4-lobed, yellow, downy; corolla 0; stamens 4-5, with yellow anthers; stigmas short, recurved, greenish yellow.

FRUIT.--Autumn of second season; acorns on stout peduncles 1/2 inch long; cup cup-shaped, with red-brown, downy scales, inclosing one-third to one-half of the nut; nut subglobose, about 1/2 inch long, dark brown, often striate; kernel very bitter.

WINTER-BUDS.--Terminal bud 1/8 inch long, ovoid, acute, l.u.s.trous, brown.

BARK.--Twigs l.u.s.trous, dark green, becoming brown; thick on old trunks, light brown and slightly fissured.

WOOD.--Heavy, hard, coa.r.s.e-grained, light red-brown, with thin, lighter colored sapwood.

DISTRIBUTION.--Of rare occurrence in Michigan. Reported in Kalamazoo, St.

Joseph and Washtenaw Counties, Lower Peninsula.

HABITAT.--Rich uplands; fertile river-bottoms.

NOTES.--Desirable for ornamental uses. Hardy. Rapid of growth.

+SUMMER KEY TO THE SPECIES OF ULMUS+

a. Leaves essentially smooth on both sides; branches often with corky, wing-like ridges; lowermost branches usually short and strongly drooping; main trunk usually continuous into the crown without dividing, giving to the tree a narrow-oblong outline. _U. racemosa_, p. 129.

aa. Leaves usually rough on one or on both sides; branches without corky ridges; lowermost branches not short, not strongly drooping; main trunk usually dividing into several large limbs, giving to the tree a more or less vase-shaped outline.

b. Leaves usually rough above, but smooth beneath, with petioles glabrous; bark of trunk gray, deeply fissured into broad, scaly ridges; inner bark not mucilaginous. _U.

americana_, p. 127.

bb. Leaves usually rough both sides, with petioles hairy; bark of trunk dark red-brown, shallowly fissured into large, loose plates; inner bark mucilaginous. _U. fulva_, p. 125.

+WINTER KEY TO THE SPECIES OF ULMUS+

a. Buds conspicuously rusty-tomentose; twigs more or less p.u.b.escent; inner bark very mucilaginous when chewed. _U.

fulva_, p. 125.

aa. Buds not conspicuously rusty-tomentose; twigs glabrous; inner bark not mucilaginous.

b. Bundle-scars usually 3; buds 1/8 inch long, glabrous; twigs without corky ridges; outline of tree vase-shaped. _U.

americana_, p. 127.

bb. Bundle-scars usually 4-6 in a curved line; buds 1/4 inch long, somewhat pilose; twigs often with corky ridges; outline of tree narrow-oblong. _U. racemosa_, p. 129.

[Ill.u.s.tration: +Slippery Elm. Red Elm+

1. Winter twig, 2.

2. Leaf, 1.

3. Flowering branchlet, 1.

4. Perfect flower, enlarged.

5. Fruit, 1.]