426 WOODY PLANTS OF MASSACHUSETTS. 
1. THE SPIRAZA TRIBE, SPIRAEA, in which the fruit is a dry seed- 
vessel or follicle. 
THE HARD HACK. SPIRAEA. L. 
The spire‘as are shrubs, or herbs from perennial roots, with 
alternate leaves, and white or rose-colored flowers, which are 
formed of a 5-cleft, persistent calyx; 5 equal petals; from 10 
to 60 stamens; 5, rarely 3 or 12, ovaries, which become so many 
1-celled follicles, distinct or rarely united at base, and contain- 
ing from 1 to 15 seeds. There are about fifty species of this 
genus, many of which are hardy plants of great beauty, culti- 
vated extensively in the gardens of Europe, and sometimes 
formed into hedges. The different species flower successively 
from spring to the end of summer. They are propagated by 
dividing the roots, by suckers, by layers or by seed. The root 
and bark generally possess astringent and tonic properties, and 
are employed in medicine and in tanning. Thirteen specics are 
found in North America, of which the following occur here. 
Sp. 1. Tse Ning Bark. SS. opulifolia. L. 
An ornamental shrub from five to seven feet high, distin- 
guished for the abundance of its showy heads of flowers, and for 
its conspicuous fruit. The stem is rugged, with loose, gray bark, 
easily detached and scaling off. The recent shoots are some- 
what angular, and green. Leaves on short footstalks, ovate, 
rounded at the end, usually with two large lobes about or below 
the middle, but often entire, doubly serrate or crenate, the serra- 
tures rounded and callous. Stipules as long as the {ootstalk, 
oblong, pointed. Flowers in nearly hemispherical heads, on a 
short stalk. Hach flower on a slender, downy thread. Calyx 
5, broad, pointed lobes. Petals round, white, with a rose tinge. 
Stamens very numerous, long, with short, purple anthers. 
It is found from Canada to Georgia and Missouri, and as far 
west as Oregon and California. 
This showy plant may be made to grow any where, in wet 
ground or dry, by cuttings thrust almost without care into the 
ground. 
