In Ky. this tree of east-central states occurs on deep fertile soils, especially in the Bluegrass region and on western lowlands with a long history of influence by megafauna and now livestock. The species also occurs locally along some river valleys within Appalachian regions. Included here as open dots are the unverified historical data of Gm and B. The closely related ovata has a more widespread range across eastern North America, mostly on uplands or drier terraces, but there is much overlap in habitat and possibly some introgression. C. laciniosa differs from ovata (F; FNA 3; W) in its generally larger nuts: mostly 4.5-6 x 4-5 cm (versus 3.5-4 x 3.5-4), laterally flattened and obovoid (versus globose but sharp-pointed at apex), with the shell typically thicker (ca. 3-6 mm versus 2 mm) and reddish-brown (versus whitish-brown). Leaflets are usually (5-)7(-9), versus (3-)5(-7) in ovata, deeper glossier green, and they lack the persistent subterminal tufts of hairs on serrations (as found in ovata and carolinae-septentrionalis). The rachis is generally persistent for 1-3 years on young vigorous trees but never so in ovata (Meijer 1972a); this character has not been mentioned in previous accounts of the species, and it is reasonable to speculate that these somewhat prickly, persistent petioles deter (or train) large herbivores from tasting the extremely bitter foliage. buds and twigs (rich in terpenoids and probably tetralones; Li et al. 2014). Bud scales are glabrous (versus partly hairy); and young twigs are pale brown to orange (versus dark grey-green to reddish). The bark is hard to distinguish but generally darker grey, with narrower and shorter peeling plates. Both species can form extraordinarily deep taproots; 8 year old seedlings of laciniosa grown in pots by JC had coiled roots up to 2.4 m long but stem height of only 0.6-0.7 m. The state champion laciniosa is in GRNP (KDF 2020): 127 cm dbh, 35 m tall, 55 m wide.