- Common Name(s):
- Cow oak, Michaux oak, Swamp chestnut oak
- Native Plants, Poisonous Plants, Trees
Quercus michauxii is a medium to large deciduous oak (part of the white oak group) with a tight, narrow, rounded crown. It typically grows to 40-60' (infrequently to 100') tall.
It's gray bark has flaky ridges. Swamp chestnut oak was a popular timber tree in the cotton belt of the Deep South during the 1800s, with its durable wood used for a number of different purposes including flooring, posts, wagons and tool handles. In addition, the wood was often split into thin but flexible strips for weaving heavy baskets used to harvest cotton from fields (hence the sometimes used common name of basket oak).
The flowers that bloom in April-May are followed by acorns (each to 1" long) which ripen in September-October. From 1/3 to 1/2 of each nut is covered by a cup with hairy, gray to light brown scales. These acorns are sweet-tasting and can be eaten directly from the tree (acorns on most oaks need to be boiled first to remove tannic acid). In addition to its wildlife value, acorns are also consumed by livestock including cows, hence the additional common name of cow oak. Acorns are typically not produced until the tree reaches 20-25 years old.
Regions: Piedmont, Coastal Plains
Seasons of Interest:
Leaves: Fall Bloom: Spring Fruit/Seed/Nut: Fall
Wildlife Value: This tree is mildly resistant to damage by deer. Host plant for Banded Hairstreak, Edward's Hairstreak, Gray Hairstreak, White-M Hairstreak, Horace's Duskywing, Juvenal's Duskywing butterflies and many moths. Acorns are eaten by woodpeckers, blue jays, ducks, small mammals, wild turkeys, white-tailed deer, and black bears.
Insects, Diseases, or Other Plant Problems: Oaks in general are susceptible to a large number of diseases, including oak wilt, chestnut blight, shoestring root rot, anthracnose, oak leaf blister, cankers, leaf spots and powdery mildew. Potential insect pests include scale, oak skeletonizer, leaf miner, galls, oak lace bugs, borers, caterpillars and nut weevils.
- 60-80 ft.
- Ornamentally insignificant flowers bloom on the Swamp chestnut oak in April-May (male in slender yellow catkins to 2-4" long and female in very short few-flowered reddish spikes).
- The Swamp chestnut oak is best grown in acidic, moist loams in full sun. It grows well in sandy soils and will tolerates some part shade but not full shade. It will also tolerate wet soils and occasional flooding.
- Pyramidal; oval to rounded; densely branched
- Poison Part:
- Acorns (seeds of nuts) and young leaves.
- Poison Delivery Mode:
- Stomach pain, constipation and later bloody diarrhea, excessive thirst and urination
- EDIBLE PARTS: Acorns (nuts) are edible after tannins are leached or boiled out. HARVEST TIME: Only collect nuts for eating from areas where you know how the property has been managed including what pesticides have been applied to the tree and the ground beneath the canopy.
- Toxic Principle:
- Gallotannins, quercitrin, and quercitin.
- CAUSES ONLY LOW TOXICITY IF EATEN.
- Found in:
- Forest or natural areas; landscape as ornamental and shade trees.
- 50-70 ft.
- Growth Rate:
- The Swamp chestnut oak has obovate leaves (to 11" long) have large rounded teeth and wavy margins. The leaves are simple, alternate and shiny green above but grayish-pubescent beneath. It's leaves are similar to those of chestnut oak (Q. montana), except for the hairy undersides. They turn dark red in fall.
NCCES plant id: 2167