14 BULLETIN 299, U. S. DEPARTMENT OF AGRICULTURE. 



in the type are spruce, hemlock, and white pine, the first two espe- 

 cially on moist situations suitable to white ash. In original forests 

 of this type white ash rarely forms more than from 1 to 5 per cent of 

 the merchantable stand, but in second-growth stands it may form 20 

 per cent or more. 



Sites on which the mixed oak and chestnut type of forest is usually 

 found (exposed upper slopes and ridges and southern slopes) have a 

 comparatively dry, hard soil often thin and very rocky. Such sites 

 are not favorable to white ash, which is fastidious in regard to soil, 

 does not readily develop a rugged, deep-going root system, as do 

 oaks and chestnut, and requires in consequence more surface moisture. 

 On this type white ash usually occurs as a subordinate, overtopped 

 tree of small diameter in comparison with the oaks and chestnut, 

 except for occasional well-developed individuals in depressions where 

 soil and moisture conditions are more favorable. It never forms 

 over 5 per cent of the stand. Ash reproduction takes place readily 

 wherever the cover is slightly broken and at the same time dense 

 enough to preserve good moisture conditions in the humus and soil; 

 but subsequent seedling development is usually poor because" con- 

 ditions are adverse. The mixed oaks and chestnut type is common 

 below 1,000 feet elevation in the glaciated hills of southern New 

 England, southern New York, Pennsylvania, and New Jersey; farther 

 south it occurs at increasing elevations, in the southern Appalachians 

 up to 4,000 feet, mostly on comparatively dry southern slopes and 

 ridges. It is common in southern Michigan, Ohio, Indiana, southern 

 Illinois, Kentucky, and Tennessee, and in the highlands of southern 

 Missouri and northwestern Arkansas. The most frequent associates 

 of white ash on this type are chestnut, red, white, scarlet, black, and 

 chestnut oaks, bitternut and pignut hickories, yellow poplar, red 

 maple, and dogwood; other species sometimes occurrhig with it are 

 swamp, white, pin, Spanish, black jack, and post oaks, black gum, 

 black walnut, shagbark hickory, ironwood, hornbeam, elm, black 

 cherry, shad bush, sugar maple, sassafras, hemlock, white, pitch, 

 and shortleaf pines, scrub pine, black and yellow birch, paper birch, 

 butternut, black locust, mulberry, beech, and red gum. 



The yellow poplar type occurs only on comparatively moist, fertile 

 sites with good drainage, such as in the hollows of small streams, 

 north slopes, and small hollows, coves and swales interspersing drier 

 oak or pine types. In old growth ash forms up to 10 per cent of the 

 stand, and in second growth up to 50 per cent. The yellow poplar 

 type is common from southern New England and southern New York 

 (below 1,000 feet elevation) to northern Florida and west to northern 

 Louisiana and eastern Arkansas and Missouri. Southward it is 

 found at increasing elevations until in the southern Appalachians it 

 reaches 3,500 feet; but it occurs also on moist, well-drained fertile 



