Species in Euphorbia

Euphorbia milii is a spiny, semi-succulent shrub in the spurge family (Euphorbiaceae), endemic to Madagascar and widely grown as an ornamental in warm regions. It usually grows up to about 1 m tall in cultivation, with stems bearing gray spines up to about 3 cm long along their ridges and leaves clustered near the stem tips. The showy red, pink or yellow parts are bracts surrounding the small true flowers (cyathia, the cup-like flower clusters typical of Euphorbia), and flowering can continue through much of the year when temperatures allow. Cut stems exude a white latex that is toxic if ingested and can irritate skin. Succulent Euphorbia species are listed in CITES (the Convention on International Trade in Endangered Species) Appendix II, but artificially propagated cultivars of this species traded in shipments of 100 or more readily recognizable plants are exempt.

Euphorbia obesa is a dwarf succulent from the Great Karoo of South Africa. It has a single, spineless, unbranched stem up to about 20 cm tall and 9 cm across, nearly spherical when young and becoming cylindrical with age. The stem is usually 8-ribbed, grey-green with dull purple transverse bands, and the rudimentary leaves soon fall. Plants are dioecious, bearing small cup-shaped cyathia near the growing tip in summer, and the capsules split explosively to scatter the seeds. Over-collecting once nearly wiped it out in the wild, and it is protected by South African nature conservation law and listed in CITES Appendix II (Convention on International Trade in Endangered Species), so international trade in plants needs export and import permits, although seed from artificially propagated plants is exempt. The milky latex released from damaged tissue is poisonous and irritates the skin and eyes.