Besides the following, some 8 others occur in southern and western North America. Type species: Acer Pseudo-plātanus L.

Leaves simple, palmately lobed.

Flowers in dense sessile lateral clusters, unfolding before the leaves.

Petals none; ovary tomentose; samaras divergent.

1.

A. saccharinum.

Petals present; ovary glabrous; samaras incurved.

Leaves pale and glabrous or but slightly pubescent beneath.

Leaves bright green above, mostly 5-lobed.

Wings of the samara broadened above the middle.

2.

A. rubrum.

Wings of the samara linear, scarcely broadened above.

3.

A.stenocarpum.

Leaves dark green above, mostly 3-lobed.

4.

A. carolinianum.

Leaves densely whitish-pubescent beneath; southern.

5.

A. Drummondii,

Flowers corymbose, lateral, unfolding with the leaves.

Flowers long-pedicelled, drooping; large trees.

Leaves pale and nearly glabrous beneath.

6.

A. Saccharum.

Leaves green and pubescent, at least on the veins, beneath.

7.

A. nigrum.

Flowers short-pedicelled, erect; shrub or small tree; western.

8.

A. glabrum.

Flowers racemed, terminal, unfolding after the leaves.

Racemes drooping; leaves finely serrate.

9.

A. pennsylvanicum.

Racemes erect; leaves coarsely serrate.

10.

A. spicatum.

Leaves pinnate.

11.

A. Negundo.

1. Acer Sacchārinum L. Silver Maple. Soft Or White Maple

Fig. 2804

Acer saccharinum L. Sp Pl. 1055. 1753.

Acer dasycarpum Ehrh. Beitr. 4: 24. 1789.

Acer eriocarpum Michx. Fl. Bor. Am. 2: 253. 1803.

A large tree with flaky bark, maximum height of 100°-120° and trunk diameter of 3°-5°. Leaves 4'-6)' long, deeply 5-lobed, the lobes rather narrow, acuminate, coarsely and irregularly dentate, truncate or slightly cordate at the base, green above, silvery. white and more or less pubescent beneath, especially when young; flowers greenish to red, in nearly sessile lateral corymbs much preceding the leaves; calyx obscurely lobed; petals none; fruiting pedicels elongating; stamens 3-6; samaras pubescent when young, divaricate, at length 2' long, the wing often 6" wide.

Along streams, New Brunswick to Florida, west to southern Ontario, South Dakota, Nebraska and Oklahoma. The samaras are frequently unequally developed. Wood hard, strong, light colored; weight per cubic foot 32 lbs. Used for furniture and floors. Maple sugar is made from the sap in small quantities. River-, silver-leaf-, creek-, water- or swamp-maple. Feb.-April.

Acer Pseųdo-Plátanus L., sycamore-maple, with terminal drooping racemes of yellowish flowers with very woolly ovaries, and deeply 3-5-lobed leaves, and Acer platanoides L., Norway maple, with terminal corymbs of greenish yellow flowers appearing with or before the 5-7-lobed leaves, commonly planted, have occasionally escaped from cultivation.

1 Acer Sacch Rinum L Silver Maple Soft Or White Ma 1146