PEA FAMILY 
apex. They come out of the bud conduplicate, yellow green, cov- 
ered with silvery down which soon disappears ; when full grown are 
dull dark green above, paler beneath. Feather-veined, midvein 
promuinens In autumn they turn a clear pale yellow. Stipules 
inear, downy, membranous at first, ultimately developing into 
hard woody prickles, straight or slightly curved. Each leaflet has a 
minute stipel which quickly falls and a short petiole. 
Flowers.—May, after the leaves. Papilionaceous. Perfect, borne 
in loose drooping racemes four to five inches long, cream-white, 
about an inch long, nectar bearing, fragrant. Pedicels slender, half 
an inch long, dark red or reddish green. 
Calyx.—Campanulate, gibbous, hairy, five-toothed, slightly two- 
lipped, dark green blotched with red, especially on the upper side 
teeth valvate in bud. 
Corolla.—Imperfectly papilionaceous, petals inserted upon a tu- 
bular disk; standard white with pale yellow blotch ; wings white, 
oblong-falcate ; keel petals incurved, obtuse, united below. 
Stamens.—Ten, inserted with the petals, diadelphous, nine infe- 
rior, united into a tube which is cleft on the upper side, superior 
one free at the base. Anthers two-celled, cells opening longitudi- 
nally. 
Pistil.—Ovary superior, linear-oblong, stipitate, one-celled ; 
style inflexed, long, slender, bearded; stigma capitate; ovules 
several, two-ranked. 
frruit.—Legume_ two-valved, smooth, three to four inches long 
and half an inch broad, usually four to eight seeded. Ripens late 
in autumn and hangs on the branches until early spring. Seeds 
dark orange brown with irregular markings. Cotyledons oval, fleshy. 
The value of Robinia pseudacacia is practically destroyed in nearly all parts 
of the United States beyond the mountain forests which are its home, by the 
borers which riddle the trunk and branches. Were it not for these insects it 
would be one of the most valuable timber-trees that could be planted in the 
northern and middle states. The character of the timber which it produces, the 
rapidity of its growth, its power to adapt itself to different soils and to repro- 
duce itself rapidly by seeds which germinate readily, and by stump and root 
shoots, would make it a most valuable tree if it could be protected from in- 
sects. Young trees grow quickly and vigorously for a number of years, but 
soon become stunted and diseased, and rarely live long enough to attain any 
commercial value. —CHARLES S. SARGENT. 
It is an interesting question why some trees grow so much 
more rapidly than others, and the explanation seems to lie in 
the character of the roots. Any tree whose principal roots 
extend just beneath the surface grows rapidly because the 
soil there is the richest ; but the cause which produces this 
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