Part 41

+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 lustrous, dark green above, paler and pubescent beneath; petioles stout, pubescent, 1/2 inch long.

FLOWERS.--May, with the leaves; monoecious; the staminate in slender, hoary-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, lustrous, brown.

BARK.--Twigs lustrous, dark green, becoming brown; thick on old trunks, light brown and slightly fissured.

WOOD.--Heavy, hard, coarse-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 pubescent; 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.

1. Winter twig, × 2. 2. Leaf, × 1. 3. Flowering branchlet, × 1. 4. Perfect flower, enlarged. 5. Fruit, × 1.]

+URTICACEAE+

+Slippery Elm. Red Elm+

Ulmus fulva Michx. [Ulmus pubescens Walt.]

HABIT.--A medium-sized tree 40-60 feet high, with a short trunk 1-2 feet in diameter; spreading branches form a broad, open, flat-topped crown.

LEAVES.--Alternate, simple, 4-7 inches long, about one-half as broad; ovate-oblong; coarsely doubly serrate; thick and firm; dark green and rough above, paler and somewhat rough beneath; petioles short, stout, hairy.