This curious slow-growing shrub, with remarkably pliable strong bark (formerly used for thongs or ropes), is scaterred across much of eastern North America, but it is not generally common; it is rare to absent on much of the Coastal Plain (K, W; Peterson 2013). D. palustris is largely restricted to woods on somewhat base-rich soils, typically iwith Acer saccharum, Quercus rubra, Lindera and Staphylea. However, growth may often be best on medium-acid soils (Peterson & Graves 2009). There may be two ploidies, with tetraploids (2n = 36) indicated in glaciated regions (FNA 6). Mapped here as open dots are the data of Gm and B. Dirca is easily overlooked and probably more widespread in Ky. than indicated by colls. Dirca spp. are small shrubs known to spread with rhizomes (Graves 2004), and with unusual small yellow-green oily drupes that may be largely dispersed by small mammals (Floden 2011). At Bernheim Forest of BULL, Walden Woods of METC and similar sites, it is locally common in open understories around the fringes of mesic wooded terraces or ravines, where deer may browse selectively on more palatable woody species. Although shoots are not clearly bitter or repellant, plants are reputedly somewhat toxic to most generalist herbivores. A. Berry (pers. comm.) has observed much evidence of winter-browsing by deer at Bernheim Forest, but the plants appear to recover well in summer. As for human effects, Rafinesque (1828) noted: "The bark and root have a peculiar nauseous smell, and unpleasant acrimonious taste; they contain an acrid resin, bitterish extractive, mucilage, &c. ... Emetic, cathartic, rubefacient, epispastic, &c. and the berries narcotic." The chemistry of Thymelaeaceae is complex and varied, with several potential mammalian toxins or skin irritants; these include tricyclic daphnane and tiglane diterpenes, esters of daphnetoxin, and coumarins (Borris et al. 1988; FNA 6). The specific chemistry of Dirca has remained rather poorly known until recent discovery of some novel cytotoxic sulphur-containing compounds (St-Gelais et al. 2015).