Sloe 



495 



appearing before the leaves in April or May, are 1.5 to 2.5 cm. across, in 3- to 

 5-flowered umbels on smooth, red pedicels i to 2 cm. long; the calyx-tube is ob- 

 conic, usually red, the lobes lanceolate, glandular- toothed, hairy on the inner 

 surface; the petals are obovate, rounded and irregularly erose, white, fading to 

 pink. The fruit, ripening in August or September, is oval or subglobose, 2.5 to 3 

 cm. long, orange to red, with a slight bloom. The skin is thick, the flesh yellow 

 and sour; the stone is oval, flattened, sharply ridged on one edge and sUghtly 

 grooved at the other. 



The fruit of the Canada plum is collected for culinary purposes, and several 

 improved forms of it are in cultivation. As an ornamental tree it is very desirable 

 on accoimt of its early, large fragrant flowers. The wood is strong, close-grained, 

 hard and brown; its specific gravity is about 0.69. 



II. SLOE — Pnmns spinosa Linnaeus 



Also called Blackthorn and Buckthorn, this is a spiny, much branched small 

 tree or shrub, native of Europe, but naturalized along roadsides, from Massachu- 

 setts to Pennsylvania, and New Jersey. Its 

 maximum height is about 9 meters, with a 

 trunk diameter of 6.5 dm. 



The bark is quite smooth and nearly 

 black; the twigs are smooth, shining, dark 

 brown, becoming dark gray. The leaves are 

 firm, ovate or oblong, 4 to 5 cm. long, blunt 

 at the apex, narrowed or rounded at the base, 

 toothed on the margin, dark green and almost 

 smooth when fully grown; the leaf-stalk is 

 about I cm. long. The flowers appear in 

 April and May before the leaves; they are 10 

 to 12 mm. across, soUtary or two together, on 

 slender, smooth pedicels about i cm. long; the 

 calyx-tube ' is bell-shaped, its lobes narrow, 

 long and blunt. The fruit, ripening in July, 

 is ovoid to globose, about 12 mm. in diameter, nearly black, with a bloom; flesh 

 thin, rather acid and astringent, edible after frost; the stone is broadly oval, 

 slightly flattened, much wrinkled, acute on one edge, ridged and grooved on the 

 other. 



The wood is hard, close-grained and red-brown; its specific gravity is about 

 0.83. It is used in Europe for the manufacture of furniture. The young trunks 

 and straight branches are made into the celebrated Blackthorn canes. As an 

 ornamental tree it has been extensively planted for hedges, but has been discarded, 

 as it suckers too profusely from the roots. A double-flowering form is very hand- 

 some and greatly admired. 



Fig. 454- — Sloe. 



