Lady Bird Johnson Wildflower Center - The University of Texas at Austin information

 Native Plant Database

Quercus havardii


Havard oak, Havard shin-oak, Shinnery oak


Fagaceae (Beech Family)



Quercus havardii (Havard oak)
Simpson, Benny
GROWTH FORM: rhizomatous shrub with a normal height of 3 feet (0.9 m) and exceptional speciments to 30 feet (9.1 m). BARK: papery, light gray. TWIGS and BUDS: brown pubescent twigs, becoming smooth with age; ovoid terminal buds are a dark reddish- brown. LEAVES: short petiole to 1⁄4 inch (6 mm); leaves are ovate or elliptical, 2 - 4 inches (51 - 101 mm) long, 3⁄4 - 2 inches (19 - 51 mm) wide; thick and with a rounded or cuneate base, margins generally have deep lobes with 2 - 3 rounded teeth on each side, apex rounded; upper surface shiny light green, lower surface has densely tawny tomentum.

This species was named for the U.S. Army surgeon and botanist, Valery Havard. Because Havard oak thrives in a harsh environment, it functions as a sand dune stabilizer and provides critical habitat for the endangered sand dune lizard (Sceloporus arenicolus). Although the acorns are an important food source for wildlife, the leaves are toxic to livestock. Use of herbicides to eradicate Havard oak has resulted in habitat loss and a drastic decline in sand dune lizard populations. The largest known Havard oak grows in Yoakum County, Texas.

Image Gallery:

21 photo(s) available

Plant Characteristics

Duration: Perennial
Habit: Shrub
Leaf Retention: Deciduous
Leaf Arrangement: Alternate
Leaf Complexity: Simple
Leaf Shape: Elliptic , Ovate
Leaf Venation: Pinnate
Leaf Margin: Dentate , Lobed
Leaf Base: Cuneate , Rounded
Breeding System: Flowers Unisexual , Monoecious
Inflorescence: Catkin
Fruit Type: Nut
Fruit: Acorns annual; solitary or paired on a peduncle up to 3⁄8 inch (10 mm), a pubescent reddish- brown cup, which covers 1⁄3 - 1⁄2 of nut; brown, ovoid nut, 1 inch (25 mm) long.
Size Class: 1-3 ft.

Bloom Information

Bloom Color: Green
Bloom Time: Mar , Apr , May

Distribution

USA: CO , NM , OK , TX , UT
Native Distribution: New Mexico, Oklahoma, and Texas.
Native Habitat: Sandy soils and sand dunes; grows in areas devoid of almost all other trees.

Growing Conditions

Water Use: Low
Light Requirement: Sun , Part Shade
Soil Moisture: Dry
Soil Description: Sandy

Last Update: 2011-09-25