=Habitat and Range.=--In its native habitat growing upon mountain
slopes, along the borders of forests, in rich soils.
Naturalized from Nova Scotia to Ontario.
Maine,--thoroughly at home, forming wooded banks along streams; New
Hampshire,--abundant enough to be reckoned among the valuable timber
trees; Vermont,--escaped from cultivation in many places; Massachusetts,
Rhode Island, and Connecticut,--common in patches and thickets and along
the roadsides and fences.
Native from southern Pennsylvania along the mountains to Georgia;
west to Iowa and southward.
=Habit.=--Mostly a small tree, 20-35 feet high, under favorable
conditions reaching a height of 50-75 feet; trunk diameter 8 inches to 2
1/2 feet; lower branches thrown out horizontally or at a broad angle,
forming a few-branched, spreading top, clothed with a tender green,
delicate, tremulous foliage, and distinguished in early June by loose,
pendulous clusters of white fragrant flowers.
=Bark.=--Bark of trunk dark, rough and seamy even in young trees, and
armed with stout prickles which disappear as the tree matures; in old
trees coarsely, deeply, and firmly ridged, not flaky; larger branches a
dull brown, rough; branchlets grayish-brown, armed with prickles;
season's shoots green, more or less rough-dotted, thin, and often
=Winter Buds and Leaves.=--Winter buds minute, partially sunken within
the leaf-scar. Leaves pinnately compound, alternate; petiole swollen at
the base, covering bud of the next season; often with spines in the
place of stipules; leaflets 7-21, opposite or scattered, 3/4-1-1/4
inches long, about half as wide, light green; outline ovate or
oval-oblong; apex round or obtuse, tipped with a minute point; base
truncate, rounded, obtuse or acutish; distinctly short-stalked;
stipellate at first.
=Inflorescence.=--Late May or early June. Showy and abundant, in loose,
pendent, axillary racemes; calyx short, bell-shaped, 5-cleft, the two
upper segments mostly coherent; corolla shaped like a pea blossom, the
upper petal large, side petals obtuse and separate; style and stigma
=Fruit.=--A smooth, dark brown, flat pod, about 3 inches long,
containing several small brown flattish seeds, remaining on the tree
throughout the winter.
=Horticultural Value.=--Hardy throughout New England in all dry, sunny
situations, of rapid growth, spreading by underground stems, ordinarily
short-lived and subject to serious injury by the attacks of borers.
Occasionally procurable in large quantities at a low rate. In Europe
there are many horticultural forms, a few of which are occasionally
offered in American nurseries. The type is propagated from seed, the
forms by grafting.
1. Winter buds.
2. Flowering branch.
3. Flower with corolla removed.
4. Fruiting branch.
=Robinia viscosa, Vent.=
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