Quercus acutissima

Lore & Background

Quercus acutissima is closely related to the Turkey oak, both classified in Quercus sect. Cerris, characterized by soft bristles around shoot buds and bristle-tipped leaf lobes. The tree has dark gray, deeply furrowed bark and leaves with 14–20 small saw-tooth-like triangular lobes per side. Its flowers are wind-pollinated catkins, and the acorns are bicolored with an orange basal half and green-brown tip, covered in a cap with soft 'mossy' bristles.

Two subspecies are accepted: Quercus acutissima subsp. acutissima, found in Japan, Korea, Manchuria, China, Vietnam, Thailand, and Cambodia; and Quercus acutissima subsp. kingii, native to Nepal, the eastern Himalayas, Myanmar, and Laos. The acorns are very bitter but eaten by jays and pigeons; squirrels eat them only when other food is scarce. The sap can leak from the trunk, attracting beetles, stag beetles, butterflies, and Vespa mandarinia.

Introduced into the United States around the 1920s, sawtooth oak has become naturalized in scattered locations in eastern North America, including states such as Florida, Missouri, New York, Alabama, and Pennsylvania. It thrives in well-drained acid soils and grows faster than many native trees, allowing it to outcompete native species. Researchers advise removing saplings and removing the species from reclamation lists to reduce potential harms.

Reader's Guide

Quercus acutissima holds significance as a widely planted wildlife food source in eastern North America, though its bitter acorns make it less suitable for that purpose than native oaks. Its fast growth and heavy acorn crops have led to its spread, and it is becoming a problematic invasive species in some areas, such as Louisiana. The wood is prone to cracking and splitting, limiting its use mainly to fencing. Charcoal from this wood is used for braziers in the Japanese tea ceremony. The species illustrates the ecological risks of introducing non-native plants for wildlife management, as it can outcompete native flora and alter ecosystems. Its classification in Quercus sect. Cerris highlights its botanical relationship with the Turkey oak, and its two subspecies reflect a broad native range across Asia.

Did You Know?

• The acorns of Quercus acutissima are very bitter but are eaten by jays and pigeons.
• The tree's sap can leak from the trunk, attracting beetles, butterflies, and Vespa mandarinia.