Part 54

d. Buds glabrous, or somewhat pubescent at the apex only; bark dark gray on the trunk. A. saccharum, p. 181.

dd. Buds hoary-pubescent; bark sometimes almost black on the trunk. A. saccharum nigrum, p. 183.

aa. Terminal buds usually 1/4-1/2 inch in length.

b. Buds reddish; opposite leaf-scars meeting.

c. Buds conspicuously stalked; bud-scales visible, 1 pair; bark longitudinally white-striped; small tree or large shrub. A. pennsylvanicum, p. 177.

cc. Buds not conspicuously stalked; bud-scales visible, 2-3 pairs; bark not white-striped; large tree. A. platanoides, p. 189.

bb. Buds bright green; opposite leaf-scars not meeting. A. pseudo-platanus, p. 191.

1. Winter twig, × 1. 2. Portion of twig, enlarged. 3. Leaf, × 1/2. 4. Staminate flowering branchlet, × 1/2. 5. Vertical section of staminate flower, enlarged. 6. Pistillate flowering branchlet, × 1/2. 7. Vertical section of pistillate flower, enlarged. 8. Fruit, × 3/4.]

+ACERACEAE+

+Striped Maple. Moosewood. Whistlewood+

Acer pennsylvanicum L.

HABIT.--A small tree at best, more often a large shrub, seldom attaining a height of more than 30 feet, with a short trunk 5-8 inches through. The striped, upright branches form a rather compact crown.

LEAVES.--Opposite, simple, 5-6 inches long and nearly as broad; 3-lobed above the middle with short, tapering lobes; palmately 3-nerved; sharply doubly serrate; rounded or heart-shaped at the base; glabrous, yellow-green above, paler beneath, turning pale yellow in autumn; petioles stout, grooved.

FLOWERS.--May-June, when the leaves are nearly full grown; usually monoecious; large, bright yellow, bell-shaped, in slender, drooping racemes 4-6 inches long; calyx 5-parted; petals 5; stamens 7-8; ovary downy.

FRUIT.--Ripens in autumn; glabrous, paired samaras in long, drooping, racemose clusters, the wings 3/4 inch long, widely divergent, and marked on one side of each nutlet by a small cavity.

WINTER-BUDS.--Bright red; terminal bud nearly 1/2 inch long, short-stalked, with bud-scales keeled; lateral buds smaller, appressed.

BARK.--Twigs light green, mottled with black, smooth; trunk and branches red-brown, marked longitudinally by broad, pale stripes.

WOOD.--Light, soft, close-grained, pinkish brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Abundant in the Upper Peninsula, extending southward as far as Roscommon County in the Lower Peninsula.

HABITAT.--Cool, rocky or sandy woods, usually in the shade of other trees.

NOTES.--In the Northwoods the green shoots are browsed by deer and moose. Valued mostly for its aesthetic qualities. Of little or no economic value.

1. Winter twig, × 1. 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.]

+ACERACEAE+

+Mountain Maple+

Acer spicatum Lam.

HABIT.--A bushy tree sometimes 25-30 feet high, with a short trunk 6-8 inches in diameter; small, upright branches form a small, rounded crown. More often a straggling shrub.

LEAVES.--Opposite, simple, 4-5 inches long and two-thirds as broad; 3-lobed above the middle, the lobes coarsely crenate-serrate with pointed teeth, the sinuses usually wide-angled and acute at the base; thin; glabrous, dark green above, covered with a whitish down beneath, turning scarlet and orange in autumn; veining prominent; petioles long, slender, with enlarged base.

FLOWERS.--June, after the leaves are full grown; polygamo-monoecious; small, yellow-green; in erect, slightly compound, many-flowered, long-stemmed, terminal racemes; calyx downy, 5-lobed; petals 5; stamens 7-8; ovary tomentose.