Ostrya chisosensis

Correll

Wrightia 3: 128. 1965.

Common names: Chisos hop-hornbeam Big Bend hop-hornbeam
Conservation concernEndemic
Synonyms: Ostrya knowltonii subsp. chisosensis (Correll) E. Murray
Treatment appears in FNA Volume 3.

Trees, to 12 m; crowns open, cylindric. Bark brownish gray, broken into narrow vertical strips. Twigs sparsely to moderately pubescent, without stipitate glands. Leaves: petiole glabrous or pubescent, without stipitate glands. Leaf blade broadly elliptic to elliptic-lanceolate, 3.5–5 × 2–3 cm, base narrowly rounded to cordate or cuneate, margins finely doubly serrate, apex obtuse to acute; surfaces abaxially sparsely pubescent, especially along veins. Inflorescences: staminate catkins 3–4 cm; pistillate catkins 0.8–1.5 cm. Infructescences 2–4 × 1.5–2.5 cm; bracts 1–1.8 × 0.5–1 cm.


Phenology: Flowering late spring.
Habitat: Streamsides and moist slopes in canyons
Elevation: 1500–2300 m

Discussion

Of conservation concern.

Ostrya chisosensis is endemic to Big Bend National Park, Texas. It appears to be related to O. knowltonii and to populations of hop-hornbeams in the mountains of western Mexico; the complex has not been studied in detail.

Selected References

None.

Lower Taxa

None.