Oaks Quercus nigra
Other Common Name(s):
Other plants called Oaks:
- Phonetic Spelling
- KWER-kus NY-gruh
- This plant has low severity poison characteristics.
- See below
- Description
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Water Oak is native to the central and eastern USA. It is a semi-evergreen tree found in forests, flood plains, and along rivers and streams or in sloped areas with drier soils. In NC, it is found from the coastal plain to the foothills of the mountains. It has a rounded to conical form, a slender, straight trunk and may grow 50 to 100 feet tall. The tree has alternate leaves with smooth or bristle-tipped margins. The leaf shape is variable and may have 0 to 5 lobes. In spring, cylindrical, male flowers and female spikes mature. The acorn requires two growing seasons to reach maturity. It is regarded as more weak-wooded than most oaks.
This tree prefers rich, medium to wet acidic soils in full sun. It is adaptable to other soil types and part shade. Great tree for naturalized areas, as a street tree or a shade tree in large areas. Also useful in wetter sites.
Insects, Diseases and Other Plant Problems: Limbs are notoriously weak, especially in high winds. Older trees susceptible to rot. Susceptible to oak wilt, often with fatal consequences. Oaks, in general, are susceptible to a large number of diseases, including 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.
Quick ID Hints:
- Leaves broad at apex, narrow tapering from middle down
- Leaf apex shallowly 3-lobed, more or lass bristle tipped
- Leaves glabrate below with axillary tufts
VIDEO created by Andy Pulte for “Landscape Plant Identification, Taxonomy and Morphology” a plant identification course offered by the Department of Plant Sciences, University of Tennessee.
- Profile Video:
- See this plant in the following landscape:
- Juniper Level Botanic Gardens: Front Shade Garden
- Cultivars / Varieties:
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- Cultivars / Varieties:
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- Tags:
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Attributes:
- Genus:
- Quercus
- Species:
- nigra
- Family:
- Fagaceae
- Uses (Ethnobotany):
- Used as timber, fuel, veneer, and plywood but it is not good for finished lumber as it splits when drying. In the case of the Native Americans, this tree was also used for food and medicine.
- Life Cycle:
- Perennial
- Woody
- Recommended Propagation Strategy:
- Seed
- Country Or Region Of Origin:
- Central & Eastern U.S.A
- Distribution:
- AL , AR , DC , DE , FL , GA , IL , KY , LA , MD , MO , MS , NC , NJ , OK , SC , TN , TX , VA. New Jersey south to Florida west to Texas, Oklahoma, Missouri north through Illinois, Kentucky, and Virginia
- Fire Risk Rating:
- low flammability
- Wildlife Value:
- Oak trees support a wide variety of Lepidopteran. You may see Imperial Moth (Eacles imperialis) larvae which have one brood per season and appear from April-October in the south. Adult Imperial Moths do not feed. Banded Hairstreak (Satyrium calanus), which have one flight from June-August everywhere but Florida where they emerge April-May. Edward's Hairstreak (Satyrium edwardsii), has one flight from May-July in the south and June-July in the north. Gray Hairstreak (Strymon melinus), has three to four flights in the south from February-November and two flights in the north from May-September. White-M Hairstreak (Parrhasius m-album) has three broods in the north from February-October. Horace’s Duskywing (Erynnis horatius) has three broods in Texas and the deep south from January-November, and two broods in the north from April-September. Juvenal’s Duskywing (Erynnis juvenalis) has one brood from April-June, appearing as early as January in Florida. Acorns are eaten by woodpeckers, blue jays, ducks, small mammals, wild turkeys, white-tailed deer, and black bears.
- Play Value:
- Attracts Pollinators
- Edible fruit
- Wildlife Food Source
- Wildlife Nesting
- Edibility:
- Acorns (nuts) are edible after tannins are leached or boiled out
- Dimensions:
- Height: 50 ft. 0 in. - 100 ft. 0 in.
- Width: 35 ft. 0 in. - 60 ft. 0 in.
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Whole Plant Traits:
- Plant Type:
- Native Plant
- Poisonous
- Tree
- Woody Plant Leaf Characteristics:
- Broadleaf Evergreen
- Deciduous
- Habit/Form:
- Conical
- Rounded
- Spreading
- Growth Rate:
- Rapid
- Maintenance:
- Medium
- Texture:
- Medium
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Cultural Conditions:
- Light:
- Full sun (6 or more hours of direct sunlight a day)
- Partial Shade (Direct sunlight only part of the day, 2-6 hours)
- Soil Texture:
- Clay
- Loam (Silt)
- Sand
- Soil pH:
- Acid (<6.0)
- Neutral (6.0-8.0)
- Soil Drainage:
- Good Drainage
- Moist
- Occasionally Dry
- Occasionally Wet
- NC Region:
- Coastal
- Mountains
- Piedmont
- USDA Plant Hardiness Zone:
- 4a, 4b, 5b, 5a, 6a, 6b, 7b, 7a, 8b, 8a, 9b, 9a
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Fruit:
- Fruit Color:
- Black
- Brown/Copper
- Fruit Value To Gardener:
- Edible
- Display/Harvest Time:
- Fall
- Fruit Type:
- Nut
- Fruit Length:
- < 1 inch
- Fruit Width:
- < 1 inch
- Fruit Description:
- 1/2 to 1-inch nearly black acorn with a flat, scaled cap that covers about 1/3 the nut. The acorn requires two growing seasons to reach maturity. Involucral bracts are in shallow cups and are imbricated. In North Carolina, the acorns from this tree are available from September to November.
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Flowers:
- Flower Color:
- Gold/Yellow
- Green
- Flower Inflorescence:
- Catkin
- Insignificant
- Flower Bloom Time:
- Spring
- Flower Description:
- Male flowers in drooping catkins and female flowers in spikes. In North Carolina, flowers are available in the month of April.
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Leaves:
- Woody Plant Leaf Characteristics:
- Broadleaf Evergreen
- Deciduous
- Leaf Color:
- Brown/Copper
- Green
- Leaf Value To Gardener:
- Showy
- Deciduous Leaf Fall Color:
- Brown/Copper
- Gold/Yellow
- Red/Burgundy
- Leaf Type:
- Simple
- Leaf Arrangement:
- Alternate
- Leaf Shape:
- Obovate
- Spatulate
- Leaf Margin:
- Entire
- Lobed
- Hairs Present:
- Yes
- Leaf Length:
- 1-3 inches
- Leaf Width:
- 1-3 inches
- Leaf Description:
- 2-4 inch bluish-green leaves are paler and have pubescence beneath. Leaves may persist throughout the winter in zones 8 and 9. Leaves are alternate, simple, narrowly obovate to spatulate, the apex is shallowly 3-lobed or no lobes, lobes are bristle-tipped to lacking bristles, the base is long and tapering from the middle of the leaf, they are entire and subcoriaceous. The midrib has two conspicuous spreading lateral veins where the leaf broadens, bearing pubescent tuft in axils.
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Bark:
- Bark Color:
- Dark Brown
- Red/Burgundy
- Surface/Attachment:
- Ridges
- Scaly
- Bark Description:
- The bark is dark and quite tight, smooth when young and later with irregular rough patches; much later developing wide, scaly ridges.
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Stem:
- Stem Is Aromatic:
- No
- Stem Buds:
- Smooth/Hairless
- Stem Bud Terminal:
- Cluster of terminal buds
- Stem Form:
- Straight
- Stem Description:
- Slender, red-brown stems. Buds are ovoid, 1/4" long, angled above and pointed, scales imbricate, and brown.
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Landscape:
- Landscape Location:
- Lawn
- Naturalized Area
- Pond
- Recreational Play Area
- Riparian
- Landscape Theme:
- Butterfly Garden
- Children's Garden
- Native Garden
- Nighttime Garden
- Pollinator Garden
- Rain Garden
- Design Feature:
- Shade Tree
- Street Tree
- Attracts:
- Butterflies
- Moths
- Pollinators
- Small Mammals
- Songbirds
- Resistance To Challenges:
- Compaction
- Deer
- Fire
- Pollution
- Salt
- Wet Soil
- Problems:
- Problem for Horses
- Weak Wood
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Poisonous to Humans:
- Poison Severity:
- Low
- Poison Symptoms:
- Abdominal pain, constipation then diarrhea (occasionally bloody), depression, frequent urination, discolored urine, jaundice; acorns can obstruct the digestive tract
- Poison Toxic Principle:
- Gallotannins, quercitrin, and quercitin.
- Causes Contact Dermatitis:
- No
- Poison Part:
- Fruits
- Leaves