Quercus marilandica #2 (Blackjack Oak)

Blackjack Oak is a compact, dense, and durable small tree native to the Midwest. This oak is the best choice for poor, dry, and shallow soils. It is rugged and adaptable, thriving in those tough, harsh areas of the landscape. It requires a well-draining site. The dark green and lustrous leaves are rusty brown beneath and are easy to distinguish from other oaks by their almost triangular shape, very narrow at the base with three large lobes rounding out the tops. The autumn foliage has no remarkable coloration, but they remain on the branches throughout winter which provides shelter for wildlife and screening in the landscape. Their overall compact size works well for limited spaces, but they are not easy to transplant due to their taproot. Transplanting and establishment is more successful when starting from a small specimen.

Species in the Red Oak group, such as Blackjack Oak, are unfortunately susceptible to Oak Wilt disease which is a fungal pathogen that is spread by bark beetles. Trees in the Red Oak group should not be pruned or otherwise wounded between April and October, and only clean, sterilized tools should be used. By spreading awareness, taking appropriate measures, and planting for succession, we can help to preserve these incredibly important trees.

Oaks are an ecological keystone genus which is invaluable to the food web and life cycles of insects, birds and other wild creatures. They are host to some 436 species of Lepidoptera, at the very top of the list for our ecoregion. Innumerable bird species rely on Oaks for their bounty of caterpillars and other insects, making them living birdfeeders. Oaks also provide cover, cavities for dens,  roosts, and nesting sites. The acorns are a necessary food supply for birds and mammals alike. Deer and rabbits do tend to browse or strip the bark of young oaks, so protection (especially through winter) is highly advised.

Sources:
Native Trees, Shrubs, & Vines by William Cullina
Manual of Woody Landscape Plants by Michael A. Dirr
Missouri Botanical Garden
Illinois Wildflowers
ODNR

Photo Credits:
Mature Individual: Jason Sturner, CC BY 2.0, via Wikimedia Commons
Leaf Detail: Jason Sturner, CC BY 2.0, via Wikimedia Commons
Fall Color: Douglas Goldman, CC BY-SA 4.0, via Wikimedia Commons