This annual wetland grass is a waterfowl favorite especially in the wetlands of California. Swamp timothy can grow in many different conditions but prefers seasonally flooded wetlands. The plants are prolific seed producers that yield over 1,000 lb of seed per acre and at over one million seeds per pound; swamp timothy readily reseeds itself year after year. Swamp timothy can also handle moderate salinity making it a great option for areas that deal with brackish water conditions. 

From the article Principles Of Wetland Management

 by the CWA 

"Target Waterfowl Food Plant: Swamp Timothy Value to Waterfowl: 

Seasonal wetlands dominated by swamp timothy are very attractive to wintering waterfowl. Swamp timothy is a low-growing (2-10” plus), seed-producing, moist-soil plant that provides sheet-water habitats when flooded. Water should be maintained at depths of 4-12” to allow optimum foraging conditions for dabbling ducks. The plant is naturally occurring on bare, poorly drained sites, but can be grown under a variety of conditions. Pintails and green-winged teal, in particular, prefer wetland habitats dominated by swamp timothy. The seeds are important to ducks arriving in early fall (August and September) as they facilitate the accumulation of fat reserves and the restoration of nutrients expended during the molt and migration. As wetland seed resources are depleted during winter, many invertebrate populations reach maximum densities and are readily available in the shallow water of swamp timothy stands. Studies indicate that midge larvae (the worm-like larvae of the midge fly) are heavily utilized by dabbling ducks in swamp timothy habitats during late winter. In addition, these shallow, open-water habitats provide excellent sites for loafing and courtship. " 

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