Heather
Heather
Heather
Heather, common name for a plant family comprising flowering plants that are widely distributed in both temperate and tropical regions of the world, and for its representative genus. The family contains about 3,350 species, which are placed in more than 100 genera and include a large number of ornamentals. Important horticultural members of the family are rhododendrons and azaleas, heath, heather, mountain laurel, and pieris. Various species produce such fruit as the bilberry, cranberry, and huckleberry.
Most members of the heath family are woody, often evergreen shrubs. Many are poisonous; many common cultivated species contain the toxin andromedotoxin, which causes vomiting and reduced blood pressure and may result in death if taken in large quantities. Azaleas, rhododendrons, and mountain laurels all contain this compound.
The flowers are characterized by four or five sepals (outer floral whorl) and four or five petals (inner floral whorl) that are fused at the base to form a tube. The stamens (male floral organs) are usually twice as numerous as the petals, and the anthers (pollen-bearing structures) open by terminal pores rather than by longitudinal slits, as they do in most families of flowering plants. The ovary (female floral organ) is usually superior (borne above and free from the other floral parts). Some tropical species are epiphytes (plants growing on other plants for support but not nourishment).
Although the order is widely distributed, its members occur mainly in cooler areas. For this reason, in tropical regions they are found mainly in mountainous areas. In addition, most members of the order will only grow in acid soils.
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