July 19, 2001

Saltcedar Potential Problem for North Dakota

Saltcedar, an invasive, nonnative plant that has caused problems in several Western states by taking over waterways and crowding out native trees and plants, has been found in North Dakota. The plant, which is a major problem in Wyoming and is found in Montana along the Yellowstone River, was found about a quarter mile into North Dakota by North Dakota Department of Agriculture weed specialists.

According to Rod Lym, a professor in the North Dakota State University plant sciences department, saltcedar forms dense stands along riverbanks and lakes. It uses large amounts of water through its extensive root system and exudes salty water from its leaves, increasing the salinity of the surrounding soil. The salt and crowding displace native trees like cottonwoods and willows normally found along waterways.

Lym says saltcedar, also called tamarisk, is a nonnative plant introduced to the U.S. in the 1800s. It has been used for erosion control as well as in shelterbelts and as an ornamental. Similar to other introduced plants such as leafy spurge, natural pests that reduce saltcedar infestations in its native range are not present in the U.S.

Saltcedar is sold in the commercial nursery trade, referred to as Showy Tamarix and other trade names. Lym says he ordered two plants from a nursery catalog, only realizing after delivery that the scientific name, Tamarix ramoissima, was the same as saltcedar. Rather than plant them in his yard as intended, Lym has the plants growing in an NDSU weed research area to observe them.

The plant, which can grow 10 to 15 feet tall, has showy purple flowers. Lym says home plantings may not be a real problem, but escapes can contribute to infestations. Nursery owners are being encouraged not to carry the species.

Saltcedar plants are capable of producing 500,000 seeds a year. The seeds are small, about the size of a flake of pepper, and are easily transported by wind and water. The seed are too small to be eaten by birds, and saltcedar thickets are not used by deer or other wildlife.

Control of saltcedar requires that the root system be destroyed. Some methods that have been used are cutting the shrub at the base and applying herbicide to the cut stump, ripping plants out by the roots with heavy equipment or spraying plants and regrowth with herbicide.

Lym says saltcedar may be added to the state’s noxious weed list. This would make it the second ornamental on the list, joining purple loosestrife.

###

Source: Rod Lym, (701) 231-8996, rod_lym@ndsu.nodak.edu
Editor: Gary Moran, (701) 231-7865, gmoran@ndsuext.nodak.edu