ROSE FAMILY 
continent prized it highly, and that it was to them an im- 
portant article of food. 
However, the Choke Cherry has recently come into ex- 
tensive cultivation on the clay flats bordering the Richelieu 
and St. Lawrence Rivers in the province of Quebec. It is 
cultivated mostly in tree form and the fruit varies greatly, 
not only in size and color but also in degree of astringency. 
Professor Sargent says: “This is the most widely dis- 
tributed North American tree. It is found within the arctic 
circle, ranging across the continent from the Atlantic to the 
Pacific, it extends southward until it reaches the Gulf states 
and northern Mexico.” 
All our wild cherries and plums carry with them a menace 
to the health and well-being of cultivated cherries and plums. 
For all are subject to a disease native to this continent, known 
as Black Knot. This warty excrescence was formerly sup- 
posed to be caused by insects, but it is now known to be the 
result of a fungus which attacks the tree and the disease 
easily passes from the native to the cultivated species. In 
many districts it is now impossible to grow cherries and 
plums because of it. The Choke Cherry is especially sub- 
ject to its attack, and this makes the tree a dangerous neigh- 
bor to orchards of cultivated fruit. 
BLACK CHERRY 
Prinus sevotina 
A tree with a stout sturdy trunk, spreading branches and round 
head, sometimes a narrow oblong head. Usually forty to fifty feet 
high, but on the slopes of the southern Alleghanies reaches the height 
of one hundred feet. Prefers a rich moist soil, but will grow on light 
sandy soil, and will also endure the winds of the sea-shore. Grows 
rapidly. Widely distributed by the birds, 
Bark.—On old trunks blackish and rough, broken into small irreg- 
ular roundish plates; on young trunks and large limbs smooth and 
shining, red brown marked with scattered lines and sometimes scpa- 
rating into horizontal bands which curl at the edges. Branchlets 
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