This difference seems to be partly due to the greater ease with which tidal wetland plants can be grown in nurseries in sufficient quantities for commercial distribution. Mitigation requirements for tidal wetlands have been imposed in many coastal regions of the United States since the mid-1970s, and the commercial market has responded by developing the methods to produce adequate quantities of nursery stock available at the appropriate planting seasons to meet the demand. The requirements for mitigation of nontidal wetlands have only more recently been enforced. Thus, in certain geographic areas of the United States, the demand for these kinds of plant materials from nurseries probably exceeds the supply, resulting in higher unit costs. When considering the use of seeds or nursery stock for restoration projects, it is best to consider only strong, nonexotic strains of plant materials.
Many nurseries carry exotic strains of common species, introduced species, or hybrid varieties.
These types of plant stock are intended for use in the home watergarden or in landscaping projects. Always check the genus and species of the plants found in the natural wetland and riparian systems in the locality and insist on purchasing these same varieties from the nursery. In addition, several States have inspection and certification programs for nursery-reared plant stock. In these cases, plants should always be obtained from properly inspected and certified dealers. In some regions of the United States, more stringent rules and regulations apply to plant stock purchased for transport across State lines.