Carolina Nature

Trees, Shrubs, and Woody Vines of North Carolina

Swamp White Oak (Quercus bicolor)

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Swamp White Oak (Quercus bicolor)

Swamp White Oak is a large overstory tree of wet areas. Quite rare in North Carolina, near the southern limit of its range, it generally grows in areas with basic bedrock; it has been found in six counties in the Piedmont, two in the Coastal Plain.

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Quercus bicolor gets its name from the typically bicolored leaves — dark green above, whitish beneath.

Leaf undersides of sun leaves are usually silvery white, but shade leaves show less contrast.

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Female flower/developing acorns.

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Developing acorns.

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Remnant male flowers.

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Leaves below may appear yellowish green or whitish, depending on whether they're shade leaves or sun leaves. At left is a comparison between the undersurfaces of sun leaves (left and right) and a shade leaf (center).

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor)

Swamp White Oak is similar to Swamp Chestnut Oak (Quercus michauxii), but the leaves are less regularly lobed; similar to White Oak (Quercus alba), but the leaf undersides are white-hairy. A hybrid White Oak × Swamp Chestnut Oak might be difficult to tell apart from a Swamp White Oak. The easiest way to tell Swamp White apart from similar oaks is to look for peeling bark on young branches — see photos below for what to look for.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor)

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor)

The photo at left shows shade leaves, which are usually not whitish beneath.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) sapling

Leaves on saplings may appear more sharply toothed.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) leaf

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) leaf underside

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) leaf underside

Detail of a leaf underside, showing a covering of fine whitish hairs.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor)

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) branch bark

One of the most distinctive traits of Swamp White Oak is the peeling bark of branches. The branch bark starts to peel when the branches are still fairly small. This is perhaps the easiest way to be sure about identifying a Swamp White Oak.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) branch bark

A larger branch, still with peeling bark.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) branch bark

A still larger branch, with the bark appearing more flaky than peeling.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) bark

Bark of a small tree.

The bark is very similar to that of White Oak and Swamp Chestnut Oak.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) bark

Bark of a large tree, high above the ground.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) bark

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor) bark

Granville Co., NC 5/23/2012.

Swamp White Oak (Quercus bicolor) bark

Bark of a medium-sized tree.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor) bark

Bark of a large tree, near the base.

Granville Co., NC 5/20/2012.

Swamp White Oak (Quercus bicolor)

Swamp White Oak is fairly common in cultivation, much more commonly seen in North Carolina as a planted tree than a wild tree. I took advantage of a visit to the Hoyt Arboretum in Portland Oregon, where the tree is not native, to photograph Swamp White Oak, which I had not seen in the wild at that time.

Planted specimen, Portland, OR 7/30/06.

Swamp White Oak (Quercus bicolor)

Planted specimen, Portland, OR 7/30/06.

More information:
Bioimages
USFS Silvics Manual
Virginia Tech Dendrology
Wisconsin Flora

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