Blueberries, cranberries and rhododendrons are cousins that thrive where soil is poor
The heather family, Ericaceae, holds about 4,250 species, from creeping heaths to rhododendron trees, and many of them flourish in acidic, nutrient-starved ground that defeats other plants. Their trick is underground partnership: fungi that wrap around and invade their roots, feeding them nitrogen and even helping them cope with heavy metals.
Spread across 124 genera, the family ranks 14th among flowering plants for number of species. It includes cranberry, blueberry, huckleberry, azaleas and the familiar heaths and heathers. Most have simple evergreen leaves, and their flowers often have fused petals forming tubes, funnels or little urns; the anthers release pollen through pores. Many species, especially blueberries and their relatives, need buzz pollination, in which a visiting insect's vibrations shake the pollen loose.
The name traces to the genus Erica, from a Greek word sometimes glossed as heather. Linnaeus formalised Erica in 1753, and Antoine Laurent de Jussieu named the family in 1789. In 2002 molecular and anatomical studies folded five former families into it, including the crowberries and the Australian epacrids, greatly widening its range of forms and places.
Ericaceae grow nearly everywhere except continental Antarctica, the high Arctic, central Greenland, inland Australia and much of the lowland tropics. They dominate peat bogs, oak-heath forests in eastern North America, and the open heathlands of Norway, Britain, the Netherlands, Spain and Portugal. Those heaths are largely human-made and survive only with regular grazing or burning. They support creatures such as the silver-studded blue butterfly, and there is evidence that nitrogen-rich rain can turn some heaths into grassland.
The fungal alliance is central to farming too: healthy fungal networks help blueberry, cranberry and wintergreen crops withstand stress, and one subfamily even draws sugars from its fungi. The United States leads the world in growing both blueberries and cranberries, with Maine producing most lowbush blueberries. Wide distribution has created naming muddles, as the American and European plants both called blueberry, or cranberry, are different species.
Source: Ericaceae
