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Key to Species — Part 29

A. Leaves simple, palmately lobed.

B. Bloom before the leaves in lateral clusters; fruit ripe in May or June.

C. Flowers red; leaves shallowly lobed, serrate, pale beneath.

(A. rubrum) RED or SWAMP MAPLE

CC. Flowers greenish yellow; leaves deeply 5-cleft, silvery white beneath.

(A. saccharinum) SILVER MAPLE

BB. Bloom after the leaves, from terminal buds; fruit ripe in autumn.

C. Petals present in flowers.

D. Flowers in erect, compact racemes.

(A. spicatum) MOUNTAIN MAPLE

DD. Flowers in loose, drooping racemes.

E. Leaves 8 to 12 inches across, deeply 5-lobed.

(A. macrophyllum) BROAD-LEAVED MAPLE

EE. Leaves 5 to 6 inches across, 3-lobed at apex;

bark stripped with white lines.(A. Pennsylvanicum) STRIPED MAPLE

DDD. Flowers in drooping terminal corymbs.

E. Leaves 7 to 9-lobed, circular.

(A. circinatum) VINE MAPLE

EE. Leaves 3-lobed or divided.

(A. glabrum) DWARF MAPLE

CC. Petals wanting; flowers in corymbs.

D. Corymbs without stalks.

E. Leaves pale beneath.

F. Lobes of leaves blunt, pubescent beneath; margins wavy.

(A. Floridanum) SUGAR MAPLE

FF. Lobes of leaves sharp, smooth beneath; margins toothed.

(A. Saccharum) SUGAR MAPLE

EE. Leaves green beneath, pubescent.

F. Branchlets slender; leaves thin, bright yellow-green.

(A. leucoderme) SUGAR MAPLE

FF. Branchlets stout, orange coloured; leaves thick, drooping, dull green.

(A. nigrum) BLACK MAPLE

DD. Corymbs on short stalks; leaves 3-lobed, pale and pubescent beneath; lobes with large rounded teeth.

(A. grandidentata) LARGE-TOOTH MAPLE

AA. Leaves pinnately compound, leaflets 3 to 5; flowers dioecious.

(A. Negundo) BOX ELDER

Opposite leaves palmately veined and lobed, and paired keys with long wings--these characters are the hallmark of the maple family the world over. No amount of "improvement" blots these out of the most ultra new variety. No other tree has both leaves and fruits likely to be confused with a maple's.

The genus Acer comprises between sixty and seventy species, well scattered over the Northern Hemisphere. China and Japan are the original home and the centre of population for them, having about thirty native maples. Twelve species are found in the Himalayas, and twelve in Europe and Asia Minor. Nine are native to North America. Of these, two are on the Pacific coast, one among the Rocky Mountains, five in the eastern half of the continent, and there is one species "at large."

Red or Scarlet Maple, Swamp Maple (Acer rubrum, Linn.)-A spreading, symmetrical tree, 80 to 120 feet high, oftener less, slender with erect branches. Bark flaky, in plates, dark grey; paler branches; twigs red. Wood pale, brownish red, hard, close grained. Buds opposite, blunt, red; flower buds clustered on side spurs. Leaves variable in size, 3 to 6 inches long, not so wide; with 3 to 5 triangular lobes, separated by triangular sinuses; margins twice cut-toothed; lining whitish, often downy; petioles long, slender, often red; autumn colours scarlet and crimson. Flowers: pistillate red, staminate orange, in earliest spring before the leaves; on same or different trees. Fruit, May, smooth, paired samaras, 1 inch long; wings divergent, hung on slender pedicels, 3 to 4 inches long, seed germinating immediately; rarely the next spring. Preferred habitat, swampy ground, borders of streams. Distribution, Eastern States to Wisconsin, Nebraska and Texas. Most common in lower Mississippi Valley. Uses: Valuable ornamental and shade tree. Wood used for gun stocks, tool handles, oars, furniture and miscellaneous woodenwares. Excellent for fuel. Occasional curly and bird's-eye logs used for veneering in cabinet work.

"The maple puts her corals on in May,

While loitering frosts about the lowlands cling,

To be in tune with what the robins sing,

Plastering new log huts' mid her branches grey;

But when the autumn southward turns away,

Then in her veins burns most the blood of spring,

And every leaf, intensely blossoming,

Makes the year's sunset pale the set of day."

-Lowell.

Who shall know the red maple better than this poet of New England? Yet it must be a sadly belated tree that blooms in May. Her May corals are the dainty keys which swing in graceful clusters from the twigs, each one red as any cock's comb.

It is fine to watch the spring come on in a region where the red maple grows. Late in March a rosy cloud lies on the wooded marshes and stream borders. Up the hillsides the same colour tells where there is a clump of these trees. The grey branches glow with their "crimson broidery" long before any but the poplar trees and pussy willows show their blossoms.

Go as early as you will to examine these maple flowers, the bees are there before you. Their motive is a selfish one, but while they swing from one bell to another in quest of nectar they dust with pollen the red forked tongues of the fertile flowers. This insures the setting of seed. The reddest flowers are the fertile ones; the sterile ones, fringed with yellow stamens, are orange coloured. The two sorts are isolated on separate branches; often on separate trees. As the leaves appear, the colour deepens. The lengthening bud scales and the opening leaves are deep crimson at first. Then come the ruddy fruits, which set the trees aglow, and which fall in early summer, leaving only the red veins of the leaves to bear the colours of the tree until late August or September. Then of a sudden the tree stands clothed in scarlet! It was not so yesterday. And one by one the leaves fall while yet fresh and smooth.