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 



Pritnus serbtina 



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 sepa- 

 rating into horizontal bands which curl at the edges. Branchlets 



128 



