This abundantly cultivated species (lettuce) does not seem to become truly established in wilder lands of North America. There are a few rather obscure or dubious records of escapes from Ky. (M). Plants known as L. serriola var. integrata Gren. & Gordon may result from hybridization of sativa and serriola (Cr). These and other Eurasian aliens in North America are diploids (2n = 18), whereas native species of Lactuca are tetraploids (2n = 34). However, there is little documentation of hybrids between species within these subgeneric divisions (Cr, FNA 19). Although some modern cultivars of sativa are often disparaged due to their low nutritional value, there are diverse physiologically active chemicals in Lactuca that can have "nutraceutical" benefits for humans (Shi et al. 2022). There is virtually no evidence of toxicity, although high tryptamine content sometimes occurs in the genus, with potential formation of toxic tryptamine alkaloids.