TREES GROWING IN RICH SOIL. 161 



CANADA PLUM. HORSE PLUM. (Plate LXXXI.) 



Primus nigra. 



Bark : light brownish grey; thin and separating into sheets. Stipules: lanceo- 

 late, or lobed and early falling. Leaves: simple; alternate, with stout petioles 

 which have one or two red glands by the blade; oval; pointed at the apex and 

 obtuse or slightly cordate at the base; coarsely serrate; when young pubes- 

 cent and tinged with red ; smooth at maturity ; not lustrous. Flowers : white; 

 turning as they fade to pink ; growing on long, reddish pedicels in lateral 

 umbels and opening before the leaves. Fruit: an orange-red drupe; oval; the 

 skin thick. Stone : clinging closely to the flesh. 



When this tree of the plum family is in bloom or hung with 

 its translucent, radiant fruit it seems to elicit continual praise. 

 In its wild state it is a thorny tree and the long spikes add much 

 to its rugged, picturesque beauty. When it, however, resigns 

 its cares in life into the hands of the horticulturist these thorns 

 become eliminated. Their original purpose which was to pro- 

 tect the fruit from the ravages of small animals is superfluous 

 in the modern garden. In fact pomologists have done much in 

 the way of diminishing them by budding with other stock and 

 selecting buds from those branches that have the fewest thorns. 

 For in cultivation thorns are no doubt an objection to a tree. 

 Pickers are annoyed by them, and during wind storms they 

 often puncture the fruit so as to render it unfit for the market. 

 Throughout the northern New England states and in Canada 

 the tree is widely cultivated, and is used as a stock upon which 

 to graft the domestic plum. As is true of many of the family 

 its fruit is quite prone to vary. Much of it finds its way into the 

 markets. It is eaten raw by many and is excellent for stewing 

 and making into preserves. 



The usual habitat of the Canada plum is in rich, alluvial soil. 

 It also grows with the hawthorns in thickets, or by the borders 

 of forests and occasionally in the neighbourhood of streams. 



