8. Carya texana Buckley (black hickory, Ozark pignut hickory)
Pl. 431 g, h;
Map 1930
Plants trees to
30 m tall (to 40 m elsewhere), but often much shorter. Bark dark gray to nearly
black, smooth or shallowly to deeply furrowed or splitting into plates but
remaining firmly attached (not exfoliating). Twigs 2–4(–5) mm thick, reddish
brown, the terminal bud 4–8 mm long, reddish brown to dark brown (often
appearing golden-frosted because of the abundant small yellow scales), the bud
scales strongly overlapping, the bractlets around the axillary buds fused to
above or below the midpoint. Leaves with the petiole and rachis glabrous or
sparsely and inconspicuously hairy, with 5 or 7 leaflets. Leaflets 3–15 cm
long, 1–6 cm wide, lanceolate to oblanceolate or narrowly obovate, straight
(appearing symmetrically tapered), the margins finely to coarsely toothed,
glabrous, the upper surface glabrous or with scattered to dense, small,
irregularly circular, reddish, peltate scales, especially when young, the
undersurface with scattered or rarely dense, branched (the branches appearing
fasciculate) hairs along the midvein or in the main vein axils, and also with
moderate to dense, larger and smaller, irregularly circular (more or less
lobed), reddish, peltate scales. Staminate catkins noticeably stalked. Fruits
3–4 cm long, 2.5–3.0 cm wide, globose to more commonly obovoid or somewhat
pear-shaped, not or only slightly flattened, smooth or with low ridges along
the 4 sutures, the husk 1–3 mm thick, splitting to the base (sometimes only
with age), with small, golden yellow scales that wear off with age. Nut not or
more commonly slightly flattened, the shell 2–3 mm thick. Seed sweet. 2n=64.
April–May.
Scattered to
common south of the Missouri River, uncommon farther north in the eastern
portion of the Glaciated Plains Division (Indiana to Georgia west to Kansas and
Texas). Mesic to dry upland forests, savannas, sand savannas, sand prairies,
edges of glades, and margins of sinkhole ponds; also pastures and roadsides;
usually on acidic substrates.
Carya texana is often difficult to separate from C.
glabra. The scales on the undersurface of the leaf in C. texana are
very heterogeneous in size and the large scales are usually crowded enough to
give the leaf a rusty appearance, while the scales on the leaves of C.
glabra are uniformly tiny, and the leaf undersurface merely looks very
finely dark-speckled. The golden-yellow appearance of the winter buds is
distinctive; the buds of C. glabra are gray or tawny, or merely dark
brown. In the spring, when buds are absent, identifications made without a
strong hand-lens or dissecting microscope should be considered tentative.
Plants with the
petiole and rachis completely glabrous have been called C. texana f. glabra
(E.J. Palmer & Steyerm.) Steyerm.