Our Botany Photo of the Day once again comes from the albums of June West, one of our Friends of the Garden. We extend our gratitude to her for yet another lovely image.
Ericaceae, commonly referred to as the heath or heather family, consists of about 100 genera and around 3000 herb, tree, dwarf shrub, and shrubby species. In general, members of the family—among them blueberry, cranberry, huckleberry, and rhododendron species—develop whorled or alternately arranged leaves and perfect (bisexual) flowers. Plants thrive in acidic soils, and most Ericaceae species form associations known as mycorrhizae, wherein specialized fungi enwrap and permeate a plants' root systems and proceed to supply them with beneficial nutrients and water. Benefits to the fungi are the carbohydrates—products of photosynthesis—supplied by the plant. This mutualistic relationship is often integral to plant survival, and is particularly so in hostile climates and habitats.
Kalmia, which receives its name from the 18th century Finnish botanist Pehr Kalm, is a small genus of 7 evergreen shrub species that are native to eastern North America and Cuba. Plants grow to a maximum height of 2.5 metres and put forth corymbs of star-shaped flowers, each of which is equipped with 5 fused petals. The fruit is a five-lobed capsule that eventually splits and disperses large numbers of small black seeds to the wind. Most parts of most plants are toxic, though some larvae of lepidopteran species, among them Coleophora kalmiella, regularly treat the plants as a source of sustenance.
Kalmia latifolia is distributed over a portion of North America that stretches from Florida to Maine and from the eastern seaboard west to Indiana and Louisiana. Plants, which thrive on rocky mountain slopes as well as in alpine forests, grow to 9 metres in height; specimens are more tree-like at low altitudes and become increasingly shrubby with elevation. In early summer, they put forth clusters of flowers that range from white to pink and red. Plants contain the toxic chemicals andromedotoxin and arbutin, and they are for that reason commonly referred to as kill-kid and sheep-poison (along with other Kalmia species).