The Genus Krameria
Family: Krameriaceae
Grayish shrubs up to about 3’, usually. Purple flowers throughout the warm season followed by spikey, attractive seed pods. Plants are semi-parasitic; they have chlorophyll and photosynthesize, but their roots invade those of other plants to usurp nutrients. Recent research suggests there is much more of an even exchange going on since parasitized plants usually continue to thrive.
Full sun, low water with good drainage, plants must be grown on a host plant—if found in nurseries (rare) there will be a native grass or some other species in the same pot. Hardiness probably to about 15°F.
The spikey Krameria fruits are usually infested with a tiny moth larva that eats the developing seed—finding fruits with viable seeds is not common. Ratany plants produce oil instead of nectar as a pollinator reward. Bees in the genus Centris usually pollinate it. Oil bees have special squeegee-like hind legs specially adapted for scraping up the oil. These bees also feed on nectar at other flowers; they provision their nests with the oil as larval food (with pollen). Butterfly larval food plant for the Mormon metalmark (Apodemia mormo) and the Mexican Metalmark (Apodemia mejicanus).
Some species of Krameria are used to make red dye, and some are used medicinally.
There are 18 species of Krameria nartive to North America to South America and West Indies. Krameria is the only living genus in the family Krameriaceae. The genus, Krameria, named for Johann Georg Heinrich Kramer (1684-1744) an Austrian physician and botanist
Typical growth form of Littleleaf Rhatany Krameria erecta. Found on sandy, gravelly plains adjacent to mountains and rocky hills from 500-5,000', photo by Max Licher, SEINET
White Rhatany (Krameria bicolor) is similar to K. erecta. It is told apart from K. erecta by the blue-green cast of the old stems, the overall canescence of the shrub, the whorled spines at the apex of the fruit, and by the petals not being connate. Photo by Eric Koberle, iNaturalist
As the name indicates, Trailing Rhatany (Krameria lanceolata) is a lower growing species, found in open areas, often in grassy sites with oak, or oak and pine from 4,000-5,500. Photo by Sue Carnahan, SEINET
Krameria fruits are spikey balls. Finding viable seed can sometimes be a challange because of a larvae that consume the seeds. Photo of Krameria erecta fruits by Liz Makings, SEINET
While the plants are definitely rugged native plants, the flowers are almost orchid-like, flower of Krameria bicolor by Dave Sussman, SEINET