11. Papaver Linnaeus, Sp. Pl. 1: 506. 1753; Gen. Pl. ed. 5, 224, 1754.
Poppy, pavot [classical Latin name for poppy; perhaps from Greek papa (pap), alluding to the thick, sometimes milky sap]
Robert W. Kiger & David F. Murray
Herbs , annual, biennial, or perennial, scapose or caulescent, from taproots; sap white, orange, or red. Stems when present leafy. Leaves: basal rosulate, petiolate; cauline alternate, proximal leaves petiolate, distal subsessile or sessile, sometimes clasping (in P . somniferum ); blade unlobed or 1-3× pinnately lobed or parted; margins entire or toothed, scalloped, or incised. Inflorescences cymiform, with flowers disposed in 1s, 2s or 3s on long scapes or peduncles; bracts present; buds nodding [erect]. Flowers: sepals 2(-3), distinct; petals 4(-6); stamens many; pistil 3-18[-22]-carpellate; ovary 1-locular, sometimes incompletely multilocular by placental intrusion; style absent; stigmas 3-18[-22], radiating on sessile, ± lobed disc, velvety. Capsules erect, 3-18[-22]-pored or short-valved immediately beneath persistent or sometimes deciduous (in P . hybridum ) stigmatic disc. Seeds many, minutely pitted, aril absent. x = 7.
Species 70-100 (16 in the flora): temperate and arctic North America, Eurasia, n, s Africa, Australia.
Papaver is rich in alkaloids, notably opiates. The genus is quite complex cytologically; in addition to diploids, there are numerous polyploid species and some that apparently are aneuploid. Most commonly, n = 7 or a multiple, and 2 n ranges from 14 to over 100. There are published chromosome counts for almost every taxon in the flora, but for the introduced species none has been made from wild-collected North American material.
The scapose poppies in the flora are native; the caulescent ones, except Papaver californicum , are introduced Eurasian ornamentals, crop weeds, and ballast waifs. All the scapose species are confined to arctic and alpine habitats. Plants of the introduced caulescent species, especially P . rhoeas , P . dubium , and P . somniferum , vary greatly in size, and surprisingly diminutive mature individuals are sometimes found, especially northward.
Kadereit, J. W. 1988. Sectional affinities and geographical distribution in the genus Papaver L. (Papaveraceae). Beitr. Biol. Pflanzen 63: 139-156. Kadereit, J. W. 1990. Some suggestions on the geographical origin of the central, west and north European synanthropic species of Papaver L. Bot. J. Linn. Soc. 103: 221-231. Kiger, R. W. 1973. Sectional nomenclature in Papaver L. Taxon 22: 579-582. Kiger, R. W. 1975. Papaver in North America north of Mexico. Rhodora 77: 410-422. Kiger, R. W. 1985. Revised sectional nomenclature in Papaver L. Taxon 34: 150-152. Novák, J. and V. Preininger. 1987. Chemotaxonomic review of the genus Papaver. Preslia 59: 1-13.