Red Oak, Quercus rubra

Red Oak

Quercus rubra

Benefits: Pollinator Benefit Graphic
Sun Shade: Plant Light Requirements Graphic
Bloom Time: Spring
Hardiness Zones: 2, 3, 4, 5, 6, 7, 8, 9
Soil Conditions: Clay, Loam
Soil Moisture: Moist, Medium, Wet
Color: Green
Fragrance: No
Height: 50 to 75 feet
Spacing: 50 feet

Red Oak, Quercus rubra, is a medium sized, deciduous tree with a rounded to broad-spreading, often irregular crown. Typically grows at a moderate-to-fast rate to a height of 50-75 feet.

Dark, lustrous green leaves (grayish-white beneath) with 7-11, toothed lobes which are sharply pointed at the tips. Leaves turn brownish-red in autumn. Insignificant flowers in separate male and female catkins appear in spring. Fruits are acorns (with flat, saucer-shaped cups) which mature in early fall. An abundant crop of acorns may not occur before this tree reaches 40 years old.

The short blooming period occurs from mid-spring to late-spring either shortly before or during the unfolding of the vernal leaves. Afterwards, fertile female flowers are replaced by acorns that take 2 years to develop. The acorns occur individually or in groups of 2-3 on short stalks about ¼-inch in length or less.

At maturity during the autumn, the acorns become ¾-1½ inches long and a little less across. The shallow cap extends about one-fourth the length of the acorn; its exterior is covered with small appressed scales that are light brown. The body of the acorn (or nut) is brown to reddish brown and smooth. The abundant meat of the nut is white and bitter.

The woody root system consists of a deep taproot and spreading lateral roots. During the autumn, the deciduous leaves turn dark red or brown, sometimes persisting on the tree into winter.

Habitats include upland woodlands, drier areas of floodplain woodlands, north- and east-facing wooded slopes, sandy woodlands, typical savannas and sandy savannas, edges of limestone glades, wooded bluffs, and high riverbanks.

This oak is often cultivated as a landscape tree. Large trees have some resistance to wildfire, while smaller trees are usually top-killed.

Easily grown in average, dry to medium moisture, acidic soil in full sun.

Prefers fertile, sandy, finely-textured soils with good drainage. This tree develops fairly quickly for an oak and it is relatively easy to transplant. Individual trees begin to produce acorns after 25-50 years and they can live 250-500 years.

 Plant Notes and Herbal Uses
  Generally a durable and long-lived tree.
  Many birds construct nests in the branches of this tree, while tree squirrels, bats, woodpeckers, and other birds have dens or nests in its cavities.
  Chlorosis (yellowing of the leaves) often occurs when soils are not sufficiently acidic.
 Further Information

 Wisconsin Fruit Trees
 Wisconsin Edible Berry Shrubs
 Widsconsin Edible Plants-Eat On The Wild Side
 8 Dandelion Recipes
 Wisconsin Native Plant Nurseries

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