The Northern Pin Oak or Hill's Oak is very similar in appearance to the very common Pin Oak. The former's leaves seem to be a little larger, less deeply lobed, and the pair of lobes just above the middle are longer than the others. Its acorns are about 1 inch long and are tapered in a deep scaly cup. It grows in upland sites on drier soils. It develops a taproot so it is difficult to transplant, so it could be carefully done in early spring B&B. Its native range is lower Michigan, northern Indiana, northern Illinois, northern Iowa, most of Wisconsin, and southeast to northcentral Minnesota. It grows about 1 foot/year and lives about 150 to 200 years. The advantage over Pin Oak is that it will grow in alkaline soils at least to 7.5 pH. So far, I've only seen two young specimens at Morton Arboretum, though Dr. Dirr in his manual reported some big ones about 80 feet high there somewhere; I'll have to find them in the future.

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