Natural infrastructure such as vegetation on dunes is one of the most important measures to protect the ocean coast from storms, coastal flooding, and erosion. At Oregon State University, two women have been studying the grasses on our coasts and have found something noteworthy.
Oregon dunes, which are present on about half of the coastline, have been home to the native grass Ammophila breviligulata, as well as the European species A. arenaria, for the past century. An OSU collaboration led by integrative biology Ph.D. candidate Rebecca Mostow and professor Sally Hacker evaluated current grass growing on the dunes using multiple analytical techniques. The findings show the beachgrasses that dominate the Northwest’s dunes have hybridized in 12 identified locations. Mostow noted that this is the only known place on Earth where those grasses have hybridized.
Although many characteristics of this hybrid grass fall between those of the parents, the height exceeds the height of either, indicating the hybrid has greater dune-building potential. Planting Ammophila grasses for nearly a century provided a base for the sand to accumulate. The grasses grew a compact rhizome mat and four-foot–tall shoots, trapping sand.
Despite the excellent sand retention properties of the grasses, species introduction always comes at a cost. The result is a change of the ecosystem. The arrival of the beach grasses resistant to pests and grazing ultimately displaced pink sand verbena and western snowy plover.