=1. Celtis occidentàlis= Linnæus. Hackberry. Plate 61. Medium to large-sized trees; bark of old trees irregularly furrowed, sometimes some of the surface warty and rough; twigs smooth or pubescent, the fruiting ones generally smooth; leaves of an ovate type on petioles 0.5-2 cm. long, the blades of fruiting twigs 5-15 cm. long, those of vegetative twigs sometimes larger, oblique or slightly cordate at base, gradually tapering to a point at apex, or long acuminate at the apex, often becoming thick at maturity, especially those exposed to full sunlight, generally smooth above at maturity, especially those of fruiting twigs, or sometimes rough, especially those of vegetative branchlets or those growing in the shade, the under surface more or less pubescent along the veins at maturity; fruit matures in late autumn, very dark red, sometimes appearing almost black, globose or somewhat oblong, generally about 9-10 mm. in diameter, borne on pedicels which are longer or up to twice as long as the petioles; the pedicels which are always ascending are straight or somewhat curved upwards; nutlets globose, a little longer than wide. =Distribution.=--Valley of the St. Lawrence River, southern Ontario, to North Dakota, and south to the Gulf States and west to Texas. More or less frequent along streams throughout the State, except in the hilly counties of the southern part of the State. It is always found in moist soil, except in the hilly counties where it may be found on wooded slopes or on high rocky bluffs bordering streams. In all of our area the species is practically confined to drainage basins, and is generally close to streams. =Remarks.=--The wood is yellowish-white and before seasoning very much resembles ash for which it was generally sold. It has good bending qualities and is now much sought after for hoops. It was formerly often known as hoop ash. The supply is now becoming scarce, but when bought sells for the same price as good white elm. Some writers include under the name _Celtis occidentalis_ only those forms which are small trees and have ovate, short-pointed leaves. This type of tree has not been found in Indiana. The form with long acuminate pointed leave which is the common form in our area, is regarded as a variety of _Celtis occidentalis_. Trees having the upper surface of the leaves very rough are called _Celtis crassifolia_ Lamarck, or are merely regarded as a variety of _Celtis occidentalis_. This form is found throughout our area. The hackberry is sometimes used as a shade tree. It can scarcely be recommended because its leaves and twigs are often affected by galls which detract from its appearance. [Illustration: Plate 62. CELTIS PUMILA var. DEAMII Sargent. Dwarf Hackberry. (× 1/2.)]