Trees of the Northern United States Part 17

7. =acer macrophllum=, Ph. (LARGE-LEAVED OR CALIFORNIA MAPLE.) Leaves very large, 8 to 10 in. broad; 5-, sometimes 7-lobed, with deep, rounded notches; lobes themselves somewhat 3-lobed and repand-notched; p.u.b.escent beneath. Flowers yellow, in erect panicles, fragrant, blooming after the leaves are expanded. Fruit large, with the seeded portion hairy; wings at about a right angle. Tree very large (100 ft. high); wood soft, whitish, beautifully veined. Twigs brown; buds green. Cultivated; from the Pacific coast, but not hardy north of 40 N. lat.i.tude.

[Ill.u.s.tration: a. platanodes.]

8. =acer platanodes=, L. (NORWAY MAPLE.) Leaves large, smooth, 5-, rarely 7-cleft, with cordate base; lobes acute, with few coa.r.s.e, sharp teeth, bright green both sides. The leaves resemble those of the Sycamore (Plata.n.u.s). Flowers a little later than the leaves in spring, in stalked corymbs, less drooping than the Sugar-maple (No. 6). Fruit with wings diverging in a straight line. A medium-sized, broad, rounded tree with brown twigs and milky juice, best seen at the bases of the young leaves. Cultivated throughout.

[Ill.u.s.tration: a. Laetum.]

9. =acer Laetum.= (COLCHIc.u.m-LEAVED MAPLE.) Leaves 5- to 7-lobed, scarcely heart-shaped at base, smooth and green on both sides; juice milky; the lobes usually without any notches or irregularities, sometimes with about three winding sinuations. Flowers in erect corymbs.

Differs from Acer platanoides in having the lobes of the leaves more nearly entire, and the fruit much smaller with wings not so broadly spreading.

[Ill.u.s.tration: a. campestre.]

10. =acer campestre=, L. (ENGLISH OR CORK-BARK MAPLE.) Leaves cordate, with usually 5 roundish lobes, sparingly crenate or rather undulated; juice milky. Racemes of flowers erect, appearing after the leaves in spring. Wings of the fruit broadly spreading; fruit ripening very late.

A low (15 to 30 ft. high), round-headed tree, with the twigs and smaller branches covered with corky bark. Occasionally cultivated; from Europe.

Var. _variegatum_ has white blotched leaves.

[Ill.u.s.tration: a. palmatum.]

11. =acer palmatum=, Thunb. (PALMATE-LEAVED j.a.pAN MAPLE.) Leaves small, smooth, palmately parted into 5 to 9 quite regularly serrated lobes.

Flowers in small umbels. A very low tree, almost a shrub; cultivated; from j.a.pan; probably hardy throughout. There are a great number of j.a.pan Maples, many of them probably varieties of this species, others hybrids.

The leaves of some are so divided and dissected as to form merely a fringe or feather. In color they range from pure green to the richest reds.

[Ill.u.s.tration: a. circinatum.]

12. =acer circinatum=, Pursh. (ROUND-LEAVED OR VINE MAPLE.) Leaves...o...b..cular, with 7 to 11 serrated, acute lobes, a heart-shaped base, reddish-green color, and both surfaces smooth. Corymbs of purplish flowers, small and hanging on long peduncles; appearing after the leaves. Wings of the fruit diverging in a straight line. A small tree or tall shrub, 10 to 30 ft. high, of spreading habit, with smooth bark, and pale brown twigs; cultivated; from the Pacific coast of North America.

[Ill.u.s.tration: a. Tartaric.u.m.]

13. =acer Tartaric.u.m=, L. (TARTARIAN MAPLE.) Leaves ovate, slightly cordate, rarely lobed, serrated, light-colored, expanding very early in the spring. Panicle of greenish-yellow flowers erect, blooming after the leaves have expanded. Wings of the fruit parallel or sometimes touching.

A small tree, sometimes shrubby in growth, of irregular form, with brown twigs; rarely cultivated; from Europe.

GENUS =26. NEGuNDO.=

Leaves pinnate, of 3 to 5 leaflets. Flowers rather inconspicuous. Fruit a two-winged key as in Acer, in drooping racemes.

[Ill.u.s.tration: N. acerodes.]

=Negundo acerodes=, Moench. (ASH-LEAVED MAPLE. BOX-ELDER.) Leaves pinnate, of 3 to 5 (rarely 7) coa.r.s.ely and sparingly toothed leaflets.

Flowers staminate and pistillate on separate trees, in drooping cl.u.s.ters rather earlier than the leaves. Fruit on only a portion of the trees; wings forming less than a right angle. A rather small (30 to 60 ft.

high), rapidly growing tree, with light pea-green twigs; wild from Pennsylvania and south, and cultivated throughout.

Var. _Californic.u.m_, Torr. and Gray (the under drawing in the figure), has leaflets more deeply cut, thicker, and quite hairy; it is occasionally cultivated.

ORDER =XVI. ANACARDIaCEae.=

(CASHEW FAMILY.)

Trees and shrubs, mainly of the tropical regions, here represented by only one genus:

GENUS =27. RHuS.=

Low trees or shrubs with acrid, often poisonous, usually milky juice, and dotless, alternate, usually pinnately compound leaves. Flowers greenish-white or yellowish, in large terminal panicles. Fruit small (1/8 in.), indehiscent, dry drupes in large cl.u.s.ters, generally remaining on through the autumn.

* Leaves simple, rounded, entire 6, 7.

* Leaves once-pinnate. (=A.=)

=A.= Twigs very hairy; rachis not winged; leaflets 11 to 31 1.

=A.= Twigs downy; rachis wing-margined; leaflets entire or nearly so 3.

=A.= Twigs smooth. (=B.=)

=B.= Rachis of leaf broadly winged; leaflets serrate 5.

=B.= Rachis not winged. (=C.=)

=C.= Leaflets 11 to 31, serrate; fruit hairy 2.

=C.= Leaflets 7 to 13, entire; fruit smooth; poisonous 4.

* Leaves twice-pinnate; variety under 2.

[Ill.u.s.tration: R. tphina.]

1. =Rhus tphina=, L. (STAG-HORN SUMAC.) Leaflets 11 to 31, oblong-lanceolate, pointed, serrate (rarely laciniate), pale beneath.

Branches and footstalks densely hairy. Fruit globular, in large, dense, erect panicles, covered with crimson hairs. Shrub or tree, 10 to 30 ft.

high. It is very common along fences and on hillsides. The wood is orange-colored and brittle.

[Ill.u.s.tration: R. glabra.]

2. =Rhus glabra=, L. (SMOOTH SUMAC.) Leaflets 11 to 31, lanceolate-oblong, pointed, serrate, smooth, glaucous white beneath.

Branches not hairy. Fruit globular, in a rather open, spreading cl.u.s.ter, covered densely with crimson hairs. A shrubby plant, 2 to 12 ft. high, found quite abundantly in rocky or barren soil throughout.

[Ill.u.s.tration: R. laciniata.]

Var. _laciniata_ is frequently planted for ornament. It has very irregularly twice-pinnate leaves drooping gracefully from the branches.

[Ill.u.s.tration: R. copallna.]

3. =Rhus copallna=, L. (DWARF MOUNTAIN SUMAC.) Branches and stalks downy; leafstalk wing-margined between the 9 to 21 oblong-lanceolate, usually entire leaflets, which are oblique at base and smooth and shining above. Wild in rocky hills throughout; often cultivated. North, a beautiful shrub; south, a tree. 2 to 25 ft. high.

[Ill.u.s.tration: R. venenata.]

4. =Rhus venenata=, DC. (POISON-SUMAC. POISON-DOGWOOD. POISON-ELDER.) Leaflets 7 to 13, obovate-oblong, entire, abruptly pointed, smooth or nearly so. Fruit small, globular, smooth, dun-colored, in loose axillary panicles hanging on late in winter; the stone striate. This is a very poisonous species (to the touch), 6 to 18 ft. high, growing in swamps. Rarely at all tree-like.