=Populus heterophylla, L.=

POPLAR. SWAMP POPLAR. COTTONWOOD.

=Habitat and Range.=--In or along swamps occasionally or often overflowed; rare, local, and erratically distributed.

Connecticut,--frequent in the southern sections; Bozrah (J. N. Bishop); Guilford, in at least three wood-ponds (W. E. Dudley _in lit._), New Haven, and near Norwich (W. A. Setch.e.l.l).

Following the eastern coast in wide belts from New York (Staten island and Long island) south to Georgia; west along the Gulf coast to western Louisiana, and northward along the Mississippi and Ohio basins to Arkansas, Indiana, and Illinois.

=Habit.=--A slender, medium-sized tree, attaining a height of 30-50 feet, reaching farther south a maximum of 90 feet; trunk 9-18 inches in diameter, usually branching high up, forming a rather open hemispherical or narrow-oblong head; branches irregular, short, rising, except the lower, at a sharp angle; branchlets stout, roundish, varying in color, degree of p.u.b.escence, and glossiness, becoming rough after the first year with the raised leaf-scars; spray spa.r.s.e.

=Bark.=--Bark of trunk dark ash-gray, very rough, and broken into loosely attached narrow plates in old trees; in young trees light ash-gray, smooth at first, becoming in a few years roughish, low-ridged.

=Winter Buds and Leaves.=--Buds conical, acute, more or less resinous.

Leaves 3-6 inches long, two-thirds as wide, densely white-tomentose when young, at length dark green on the upper side, lighter beneath and smooth except along the veins; outline ovate, wavy-toothed; base heart-shaped, lobes often overlapping; apex obtuse; leafstalk long, round, downy; stipules soon falling.

=Inflorescence.=--April to May. Sterile catkins when expanded 3-4 inches long, at length pendent; scales cut into irregular divisions, reddish; stamens numerous, anthers oblong, dark red: fertile catkins spreading, few and loosely flowered, gradually elongating; scales reddish-brown; ovary short-stalked; styles 2-3, united at the base; stigmas 2-3, conspicuous.

=Fruit.=--Fruiting catkins spreading or drooping, 4-5 inches long: capsules usually erect, ovoid, acute, shorter than or equaling the slender pedicels: seeds numerous, white-hairy.

=Horticultural Value.=--Not procurable in New England nurseries or from collectors; its usefulness in landscape gardening not definitely known.

[Ill.u.s.tration: PLATE XVI.--Populus heterophylla.]

1. Winter buds.

2. Branch with sterile catkin.

3. Sterile flower.

4. Scale of sterile flower.

5. Branch with fertile catkin.

6. Fertile flower.

7. Fruiting branch with mature leaves.

=Populus deltoides, Marsh.=

_Populus monilifera, Ait._

COTTONWOOD. POPLAR.

=Habitat and Range.=--In moist soil; river banks and basins, sh.o.r.es of lakes, not uncommon in drier locations.

Throughout Quebec and Ontario to the base of the Rocky mountains.

Maine,--not reported; New Hampshire,--restricted to the immediate vicinity of the Connecticut river, disappearing near the northern part of Westmoreland; Vermont,--western sections, abundant along the sh.o.r.es of the Hoosac river in Pownal and along Lake Champlain (W. W.

Eggleston); in the Connecticut valley as far north as Brattleboro (_Flora of Vermont_, 1900); Ma.s.sachusetts,--along the Connecticut and its tributaries; Rhode Island,--occasional; Connecticut,--occasional eastward, common along the Connecticut, Farmington, and Housatonic rivers.

South to Florida; west to the Rocky mountains.

=Habit.=--A stately tree, 75-100 feet in height; trunk 3-5 feet in diameter, light gray, straight or sometimes slightly inclined, of nearly uniform size to the point of branching, surmounted by a n.o.ble, broad-spreading, open, symmetrical head, the lower branches ma.s.sive, horizontal, or slightly ascending, more or less pendulous at the extremities, the upper coa.r.s.e and spreading, rising at a sharper angle; branchlets stout; foliage brilliant green, easily set in motion; the sterile trees gorgeous in spring with dark red pendent catkins.

=Bark.=--In old trees thick, ash-gray, separated into deep, straight furrows with rounded ridges; in young trees light yellowish-green, smooth; season's shoots greenish, marked with pale longitudinal lines.

=Winter Buds and Leaves.=--Buds large, conical, smooth, shining. Leaves 3-6 inches long, scarcely less in width, variable in color and shape, ordinarily dark green and shining above, lighter beneath, ribs raised on both sides; outline broadly ovate, irregularly crenate-toothed; apex abruptly acute or ac.u.minate; base truncate, slightly heart-shaped or sometimes acute; stems long, slender, somewhat flattened at right angles to the plane of the blade; stipules linear, soon falling.

=Inflorescence.=--April to May. In solitary, densely flowered catkins; bracts lacerate-fringed, each bract subtending a cup-shaped scale; stamens very numerous; anthers longer than the filaments, dark red: fertile catkins elongating to 5 or 6 inches; ovary ovoid; stigmas 3 or 4, nearly sessile, spreading.

=Fruit.=--Capsules ovate, rough, short-stalked; seeds densely cottony.

=Horticultural Value.=--Hardy in southern-central New England; grows rapidly in almost any soil and is readily obtainable in nurseries. Where an immediate effect is desired, the cottonwood serves the purpose excellently and frequently makes very fine large individual trees, but the wood is soft and likely to be broken by wind or ice. Usually propagated from cuttings.

[Ill.u.s.tration: PLATE XVII.--Populus deltoides.]

1. Winter buds.

2. Branch with sterile catkins.

3. Sterile flower, back view.

4. Sterile flower, front view.

5. Scale of sterile flower.

6. Fertile flower.

7. Fruiting catkin.

8. Branch with mature leaves.

9. Variant leaf.

=Populus balsamifera, L.=

BALSAM. POPLAR. BALM OF GILEAD.

=Habitat and Range.=--Alluvial soils; river banks, valleys, borders of swamps, woods.

Newfoundland and Nova Scotia west to Manitoba; northward to the coast of Alaska and along the Mackenzie river to the Arctic circle.

Maine,--common; New Hampshire,--Connecticut river valley, generally near the river, becoming more plentiful northward; Vermont,--frequent; Ma.s.sachusetts and Rhode Island,--not reported; Connecticut,--extending along the Housatonic river at New Milford for five or six miles, perhaps derived from an introduced tree (C. K. Averill, _Rhodora_, II, 35).

West through northern New York, Michigan, Minnesota, Dakota (Black Hills), Montana, beyond the Rockies to the Pacific coast.

=Habit.=--A medium-sized tree, 30-75 feet high, trunk 1-3 feet in diameter, straight; branches horizontal or nearly so, slender for size of tree, short; head open, narrow-oblong or oblong-conical; branchlets mostly terete; foliage thin.

=Bark.=--In old trees dark gray or ash-gray, firm-ridged, in young trees smooth; branchlets grayish; season's shoots reddish or greenish brown, spa.r.s.ely orange-dotted.

=Winter Buds and Leaves.=--Buds 3/4 inch long, appressed or slightly divergent, conical, slender, acute, resin-coated, sticky, fragrant when opening. Leaves 3-6 inches long, about one-half as wide, yellowish when young, when mature bright green, whitish below; outline ovate-lanceolate or ovate, finely toothed, gradually tapering to an acute or ac.u.minate apex; base obtuse to rounded, sometimes truncate or heart-shaped; leafstalk much shorter than the blade, terete or nearly so; stipules soon falling. The leaves of var. _intermedia_ are obovate to oval; those of var. _latifolia_ closely approach the leaves of _P. candicans_.

=Inflorescence.=--April. Sterile 3-4 inches long, fertile at first about the same length, gradually elongating, loosely flowered; bracts irregularly and rather narrowly cut-toothed, each bract subtending a cup-shaped disk; stamens numerous; anthers red: ovary short-stalked; stigmas two, 2-lobed, large, wavy-margined.

=Fruit.=--Fruiting catkins drooping, 4-6 inches long: capsules ovoid, acute, longer than the pedicels, green: seeds numerous, hairy.

=Horticultural Value.=--Hardy throughout New England; grows in all excepting very wet soils, in full sun or light shade, and in exposed situations; of rapid growth, but subject to the attacks of borers, which kill the branches and make the head unsightly; also spreads from the roots, and therefore not desirable for ornamental plantations; most useful in the formation of shelter-belts; readily transplanted but not common in nurseries. Propagated from cuttings.