Commonly known as salt cedar, several Tamarisk species (Tamarix spp.) flourish in the United States. Introduced from Eurasia in the 1800s as a means of erosion control, the tree-like shrubs became useful as windbreaks, and soon gained acceptance by horticulturalists as garden ornamentals. Filled with delicate pink flowers in spring, salt cedars occasionally take on rich, molten colors in autumn, adding considerable interest to a landscape or garden.
Unfortunately, salt cedars are aggressive: spreading into riparian areas of the American West as well as along the beaches, tidal marshes, and wetlands of coastal states. Able to survive the cold, they can be found around the Great Lakes, and even as far north as Toronto and Montreal.
Where conditions suit them they spread easily, consuming large amounts of water in the process. As they pull water from saline soils, excess salt accumulates in their leaves before being excreted through glands on the leaves’ underside: the source of the plant’s common name. Sometimes, leaves become encrusted with salt crystals before dropping to the ground. When that happens, high concentrations of salt accumulate in the soil; even two inches of salt-encrusted leaf litter beneath the trees can displace native plants, or prevent their establishment
Despite their invasive status, and despite on-going attempts to control or eradicate them, there’s no denying the salt cedars’ attractiveness. Like other non-native plants introduced to please the eye, their presence may have resulted in some unintended consequences, but they certainly are pretty.