Sand dune stabilization is a coastal management practice designed to prevent erosion of sand dunes. Sand dunes are common features of shoreline and desert environments. Dunes provide habitat for highly specialized plants and animals, including rare and endangered species. They can protect beaches from erosion and recruit sand to eroded beaches. Dunes are threatened by human activity, both intentional and unintentional (see sand theft and sand mining). Countries such as the United States, Australia, Canada, New Zealand, the United Kingdom, and Netherlands, operate significant dune protection programs. Stabilizing dunes involves multiple actions. Planting vegetation reduces the impact of wind and water. Wooden sand fences can help retain sand and other material needed for a healthy sand dune ecosystem. Footpaths protect dunes from damage from foot traffic. The location of the dune limits the types of plant that can thrive there. Beach dunes consist of the foredune, the angled side which faces the ocean, the sand plain at the top of the dune, which may or may not be present, and the backdune, the angled side that faces away from the ocean. Foredune flora Plants that thrive on the foredune must be tolerant to salt spray, strong winds, and burial by blowing/accumulating sand. Typical vegetation includes Ammophila arenaria, Honckenya peploides, Cakile maritima, and Spartina coarctata. Backdune flora Plants which thrive on the broad dune plain and backdune grow together into dense patches termed dune mats that hold the dune together. Vegetation typical of the plain and backdune include Hudsonia tomentosa, Spartina patens, Iva imbricata, and Eregeron glaucus. Introduced species can out compete native plants and disrupt animal life, making them formally "invasive species". Shrub stage The above species are herbaceous plants. After they have rooted and developed fully, a second stage, the "shrub stage", can begin. During this phase, larger plants with deeper root systems can be planted. Examples are Empetrum nigrum, Ilex vomitoria, and Vaccinium ovatum. The shrub stage is usually the final phase and may last for short or long periods of time depending on microclimatic conditions such as distance from the shoreline, availability of groundwater, or salt spray effects.. Coastal management A single beach may be divided into segments with different owners. Gaining agreement among all owners complicates the process of stabilizing the dunes. Without agreement, some parts of the dune may go unplanted, while others host visually appealing plants that do little to stabilize the dune. Inconsistent