338 TREES OF MINNESOTA. ^ ... 



goods, wood type, and engravers' wood, butter molds, croquet 

 sets, crutches, umbrella sticks and canes, kegs, sugar hogsheads, 

 churns, measures, faucets, wood screws and gauges charcoal, in 

 turnery for handles of tools and clothes pins, and in ship build- 

 ing for keels, etc. In the United States shoe lasts and pegs 

 are made almost exclusively from this wood. Accidental forms 

 in which the grain is beautifully curled and contorted, known 

 as "curled maple" and "bird's-eye maple" are common, and 

 highly prized for cabinet making. The ashes of the wood are 

 rich in alkili, and yield large quantities of potash. The wood of 

 the Minnesota and Wisconsin Sugar Maple is so very hard and 

 uneven in grain that it has not been worked much into lumber, 

 and the supply of Hard Maple lumber manufactured here is 

 mostly imported from Michigan, where clear stock is more 

 plentiful. Maple sugar is almost the exclusive product of this 

 tree. It is made by evaporating the sap, which is procured by 

 tapping the trees in early spring some weeks before the buds 

 begin to swell. About three or four gallons of sap are usually 

 required to make a pound of sugar. Two or three pounds of 

 sugar per tree is the average yield, but large isolated trees will 

 often yield very much more than this. When tapping is prop- 

 erly done it does not seriously impair the health of the tree. 



Acer platanoides. Norway Maple. 



Leaves broad, smooth, thin, bright green on both sides, their 

 five short taper-pointed lobes set with coarse taper-pointed teeth. 

 Flowers numerous, with both sepals and petals distinct, yellow- 

 ish, conspicuous, in erect corymbose clusters terminating the 

 shoot of the season, or some from lateral buds appearing with 

 the leaves. Fruit in drooping clusters, with large divergent 

 wings spreading two and one-half to three and one-half inches, 

 ripening in autumn. Buds blunt pointed and rather divergent; 

 new growth often reddish; juice milky. Resembles the Sugar 

 Maple in general appearance, but is easily distinguished from it. 

 Its leaves hold green later than other maples, and turn a bright 

 yellow in autumn. A round-headed tree attaining a height of 

 from thirty to sixty feet. 



Distribution. Northern and central Europe and Asia. 



Propagation. By seeds for the species and by budding, graft- 

 ing or layering for the varieties. 



