Sawtooth Oak (Quercus acutissima)

A deciduous tree from the Beech Family (Fagaceae)

Sawtooth Oak, native to Japan, China, and Korea, is a species introduced because of its rapid establishment and heavy fruit production at an early age, serving as a source of food in late summer and throughout autumn for wildlife. Large birds (crows, bluejays, turkeys), squirrels, deer, racoons, opossums, and other mammals love the large, abundant crops of acorns, which are borne heavily every other year, if not every year.

This Oak is easy to identify by its pyramidal shape in youth, striated young bark, retained winter foliage, acorns with frilled caps, and finely serrated leaves (from which it gets its common name). It is planted throughout most of Ohio, and may reach 60 feet tall by 60 feet wide at maturity, when found in the open. As a member of the Red Oak group and the Beech Family, it is related to the Beeches, Chestnuts, and other Oaks.

Planting Requirements - Sawtooth Oak prefers moist, well-drained, acidic soils of moderate fertility, but adapts well to relatively poor, dry soils of neutral or slightly alkaline pH. It thrives in full sun to partial sun (but is shade tolerant in youth) and is grown in zones 5 to 9.

Potential Problems - Sawtooth Oak is basically disease and pest free, which is somewhat remarkable for an introduced species. In very high pH soils, it develops chlorotic leaves. This oak tends to retain its spreading lower branches moreso as compared to other Oaks, so limbing up in urban situations will be necessary at a fairly young age.

Leaf Identification Features

Sawtooth Oak has alternate, glossy, oblong, non-lobed leaves with many fine serrations that terminate in a bristle-tip (hence the common name Sawtooth). Fall color is late, often having elements of yellow before terminating in a rich tan-brown color in late autumn.

Leaves at the tips of twigs fall off, but most others remain on all winter and only abscise with the swelling of twigs the following spring, just before bud break. As a result, the wind rustles the persistent leaves during winter, and this tree may serve as a non-evergreen windbreak for wildlife seeking refuge.

Other Identification Features

Sawtooth Oak is monoecious, having pendulous pollen-bearing catkins in mid-spring that are the "showy" flowers easily seen. By being a member of the Red Oak group, the miniature female flowers that are fertilized on the same tree take two years to develop. However, they are not obvious until the second year, when they fill out during the summer and ripen early as compared to most other Oaks, in late summer and early autumn, often with very heavy fruit crops.

Among the Oaks, the acorn of Sawtooth Oak is among the most interesting. While the nut is readily consumed by wildlife, the frilled cap (actually composed of long recurved scales) that originally covers about half of the nut falls away and persists on the ground into the following year.

Twigs of all Oaks terminate in a cluster of buds, and those of Sawtooth Oak are checkered. This somewhat matches the young branches, which have a muscled, striated bark.

As the bark matures, it becomes the ragged, ridged, and furrowed dark gray to gray-brown bark that is characteristic of members of the Red Oak group.