OLEÀCEAE. The Olive Family.
| Leaves compound; fruit dry, a samara | [1 Fraxinus.] |
| Leaves simple; fruit fleshy, a drupe | [2 Adelia.] |
Trees with opposite, odd-pinnate leaves; flowers appear in April or May in clusters from the axils of last year's leaves, the staminate and pistillate on different or sometimes on the same tree; fruit a 1-seeded samara.
| Bark of mature trees furrowed; fruit not winged to the base. | |
| Body of fruit robust, round and rather abruptly passing into the wing; the body rarely winged 1/3 its length. | |
| Shoots and axis of leaves smooth | [1 F. americana.] |
| Shoots and axis of leaves velvety pubescent, at least when young | [2 F. biltmoreana.] |
| Body of fruit flattened and gradually passing into the wing; the body usually winged more than 1/3 its length. | |
| Shoots glabrous, or practically so | [3 F. lanceolata.] |
| Shoots velvety pubescent, at least when young. | |
| Calyx of fruit less than 3 mm. long; body of samara just below the wing less than 3 mm. wide, rarely 4 mm. wide, usually 1.5-2.5 mm. wide; samaras 3-4.5 cm. long | [4 F. pennsylvanica.] |
| Calyx of fruit more than 3 mm. long, generally 4-5 mm. long; body of samara just below the wing more than 3 mm. wide, usually 4-5 mm. wide; samaras generally 4-6 cm. long | [5 F. profunda.] |
| Bark of mature trees scaly or flaky; fruit winged to the base. | |
| Twigs usually 4 angled; leaflets on very short stalks | [6 F. quadrangulata.] |
| Twigs round; leaflets sessile | [7 F. nigra.] |
1. Fraxinus americàna Linnæus. White Ash. Gray Ash. [Plate 124.] Large trees with deeply furrowed bark; twigs smooth, greenish gray and often covered with a bloom; leaves generally 2-3.5 dm. long, rachis smooth; leaflets 5-9, usually 7, generally 5-14 cm. long, on stalks generally 0.3-1 cm. long, the terminal one on a stalk 2-4 times as long, leaflets ovate to narrow-oblong, narrowed, rounded or oblique at base, short or long acuminate at apex, sometimes merely acute, margins entire or irregularly serrate, usually not serrated to the base, teeth short, dark green and smooth above, glaucous beneath, sometimes almost green beneath about Lake Michigan and in the northern tier of counties, usually pubescent beneath along the midrib and along the veins, sometimes glabrous; calyx persistent on the fruit, about 1 mm. long; fruit ripens in September and October, linear, 3-4.5 cm. long, variable in size and shape, body of samara cylindrical, somewhat narrower than the wing and usually 1/3-1/4 the length of the samara, each face of the body usually striated longitudinally with about 8 faint lines; wing terminal, generally about 0.5 cm. wide, pointed or notched at apex.
Distribution.—Nova Scotia to Minnesota and south to the Gulf. Frequent to common in all parts of Indiana. It is the most abundant in the northern two-thirds of the State, where it is associated principally with beech, sugar maple, linn, slippery elm and red oak. In the hilly part of the State it is found principally near water courses and in ravines, and rarely on the white and black oak ridges. It is rarely found in the low "flats" of the southeast part of the State, or in the shingle oak bottoms along the Patoka River.
Remarks.—The foliage of the white ash is quite variable in the texture of the leaflets. Leaflets on some trees are quite thin while those of other trees are thick and leathery, and no doubt would be classed by Sargent as variety subcoriacea[68].