HABITAT.--Prefers low, moist, rich soil of river-bottoms, but does well on gravelly soils and uplands.

NOTES.--Very variable. A very good shade tree because of its dense foliage. It is claimed by some that the finest grades of maple sugar are made from the sap of this tree.

[Ill.u.s.tration: +Silver Maple. Soft Maple+

1. Winter twig, 1.

2. Portion of twig, enlarged.

3. Leaf, 1/2.

4. Staminate flowering branchlet, 1.

5. Staminate flower, enlarged.

6. Pistillate flowering branchlet, 1.

7. Pistillate flower, enlarged.

8. Fruit, 1/2.]

+ACERACEAE+

+Silver Maple. Soft Maple+

_Acer saccharinum L._ [_Acer dasycarpum Ehrh._]

HABIT.--A beautiful tree, growing to a height of 60-80 feet, with a trunk diameter of 2-4 feet, usually separating near the ground into 3-4 upright stems which are dest.i.tute of branches for a considerable distance. Usually the long, slender branches bend downwards, but with their tips ascending in a graceful curve. Crown broad, especially in its upper portion.

LEAVES.--Opposite, simple, 3-6 inches long and nearly as broad; usually 5-lobed by narrow, acute sinuses which extend nearly to the midrib, the lobes often sublobed, sharply toothed; light green above, silvery white beneath, turning pale yellow in autumn; petioles long, slender, drooping.

FLOWERS.--March-April, before the leaves; polygamo-monoecious or dioecious; small, yellow-green, in crowded, sessile umbels; calyx 5-lobed (sometimes each lobe again divided); corolla 0; stamens 3-7; ovary hairy.

FRUIT.--May, germinating as soon as it reaches the ground; paired samaras, large, glabrous, curving inwards, one samara often aborted.

WINTER-BUDS.--Dark red, blunt; the terminal about 1/4 inch long, with bud-scales often apiculate at the apex; flower-buds cl.u.s.tered on side spurs.

BARK.--Twigs smooth, red-gray, l.u.s.trous; young trunks gray, smooth; old trunks dark gray, more or less furrowed, separating into thin, loose scales.

WOOD.--Hard, strong, close-grained, rather brittle, perishable, pale brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Lower Peninsula south of Saginaw Bay.

HABITAT.--Prefers low, rich bottom-lands, subject to occasional inundation, but not in swamps.

NOTES.--A rapid grower, adapting itself to a variety of soils. Does not do well on dry, elevated ground. The first tree to blossom in early spring.

[Ill.u.s.tration: +Red Maple. Soft Maple+

1. Winter twig, 1.

2. Portion of twig, enlarged.

3. Leaf, 1.

4. Fascicle of staminate flowers, 1.

5. Staminate flower, enlarged.

6. Fascicle of pistillate flowers, 1.

7. Pistillate flower, enlarged.

8. Fruit, 3/4.]

+ACERACEAE+

+Red Maple. Soft Maple+

_Acer rubrum L._

HABIT.--A medium-sized tree 40-50 feet high, occasionally in swamps 60-75 feet; trunk 1-3 feet in diameter; upright branches, which form a low, rather narrow, rounded crown.

LEAVES.--Opposite, simple, 3-4 inches long and nearly as broad; 3-5-lobed by broad, acute sinuses, the lobes irregularly doubly serrate or toothed; glabrous, green above, whitish and generally glabrous beneath, turning bright scarlet in autumn; petioles long, slender.

FLOWERS.--March-April, before the leaves; polygamo-monoecious or dioecious; in few-flowered fascicles on shoots of the previous year, the pistillate red, the staminate orange; sepals 4-5; petals 4-5; stamens 5-8; ovary smooth.

FRUIT.--May-June, germinating immediately after reaching the ground; samaras small, on drooping pedicels 2-4 inches long; wings about 1 inch long, diverging at about a right angle.

WINTER-BUDS.--Dark red, blunt; terminal bud about 1/8 inch long, with bud-scales rounded at the apex; flower-buds cl.u.s.tered on side spurs.

BARK.--Twigs bright red, l.u.s.trous, becoming smooth and light gray on the branches; old trunks dark gray, ridged, separating into plate-like scales.

WOOD.--Heavy, close-grained, not strong, light brown, with thick, lighter colored sapwood.

DISTRIBUTION.--Throughout the entire state.

HABITAT.--Prefers swamp-lands or banks of streams; rarely found on hillsides.

NOTES.--A valuable shade and ornamental tree. Sugar has been made in small quant.i.ties from the sap.

[Ill.u.s.tration: +Norway Maple+

1. Winter twig, 1.

2. Leaf, 1/2.

3. Raceme of staminate flowers, 1/2.

4. Staminate flower, enlarged.

5. Raceme of pistillate flowers, 1/2.

6. Pistillate flower, enlarged.

7. Fruit, 1/2.]

+ACERACEAE+

+Norway Maple+