Thinopyrum distichum, commonly known as Sea Wheat, is a perennial grass species with significant ecological roles in coastal environments. This species is a member of the Triticeae tribe within the grass family Poaceae, a group that includes many important cereal crops. Sea Wheat is particularly adapted to saline conditions, making it a key component of salt marsh and dune ecosystems. Physically, Thinopyrum distichum is a robust, caespitose (clump-forming) grass. It typically grows to a height of 30 to 80 centimeters, though it can occasionally reach up to 1 meter. The stems, or culms, are erect and somewhat rigid. Its leaves are linear, typically 10 to 30 centimeters long and 3 to 6 millimeters wide, with a glaucous or bluish-green appearance. The leaf sheaths are smooth, and the ligules are short and membranous. The inflorescence is a spike, resembling that of wheat, hence its common name. The spikes are erect, 5 to 15 centimeters long, and composed of multiple spikelets arranged alternately along the central axis. Each spikelet contains 2 to 5 florets. The glumes are lanceolate, and the lemmas are awned, giving the spike a somewhat bristly appearance. The caryopses, or grains, are oblong and typically enclosed within the lemma and palea. The native distribution of Thinopyrum distichum is primarily along the coastlines of the North Atlantic, including Europe and parts of North America. It thrives in maritime environments, colonizing sandy beaches, salt marshes, and coastal dunes. Its tolerance to salt spray, inundation by seawater, and sandy, nutrient-poor soils allows it to establish in habitats that are inhospitable to many other plant species. Cultivation requirements, where attempted for ecological restoration or research, would necessitate well-drained soils with high salinity and exposure to coastal conditions. Thinopyrum distichum plays a vital role in stabilizing coastal dunes and preventing soil erosion through its extensive root system. Its presence contributes to the biodiversity of salt marsh ecosystems by providing habitat and food for various invertebrates and birds. While not a primary agricultural crop, its genetic material has been of interest in breeding programs for developing salt-tolerant cereal varieties due to its remarkable halophytic nature. Its ability to thrive in saline environments is a significant adaptation, allowing it to sequester excess salts and maintain physiological functions under stressful conditions. This resilience makes it a valuable subject for scientific study in plant physiology and adaptation to environmental extremes.