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Recent emphasis on restoration of degraded wetland and riparian areas in the Intermountain area has created a demand for planting stock of native sedges (Carex spp.) and rushes (Juncus spp.). There are ≈ 100 native sedges and 20 rushes in this region, few of which have been propagated in the past. Many grow in moist to wet areas and are adaptable to water gardens. Some are upland species, capable of growing in drier areas and landscape plantings. Members of both genera are easily propagated vegetatively, but there is increasing interest in seed propagation of these species, with nurseries installing seed production blocks of common sledges. Longevity of sedge and rush seed in sealed, dry storage is unknown, but we have noted little or no viability loss in 15 species after 3 years of storage. Viability testing is used to estimate seed quality because rules for testing seeds of each species are not yet available. Researchers are beginning to examine germination requirements of individual species. Germinability and dormancy vary widely among species and seedlots, but germination is frequently improved by exposure to light and alternating incubation temperatures. Developing seedlings grow rapidly, producing dense, fibrous root systems.
Native grass, forb, and shrub seed is needed to restore rangelands of the U.S. Intermountain West. Fernleaf biscuitroot [Lomatium dissectum (Nutt.) Mathias & Constance] is a desirable component of rangelands. Commercial seed production is necessary to provide the quantity and quality of seed needed for rangeland restoration and reclamation efforts. Fernleaf biscuitroot has been used for hundreds if not thousands of years in the western United States as a source of food and medicine. Knowledge about fernleaf biscuitroot is confined to ethnobotanical reports, evaluation of some of its chemical constituents, and its role in rangelands. Products derived from fernleaf biscuitroot are sourced from wild plant populations. Little is known about fernleaf biscuitroot cultivation or its seed production. Variations in spring rainfall and soil moisture result in highly unpredictable water stress at flowering, seed set, and seed development of fernleaf biscuitroot. Water stress is known to compromise seed yield and quality for other seed crops. Irrigation trials were conducted at the Oregon State University Malheur Experiment Station at Ontario, OR, a location within the natural environmental range of fernleaf biscuitroot. It was anticipated that supplemental irrigation would be required to produce a seed crop in all years. Fernleaf biscuitroot was established through mechanical planting and cultivation on 26 Oct. 2005 in a randomized complete block design with four replicates; plot size was 9.1 m × 3.04 m wide. Irrigation treatments were 0 mm, 100 mm, and 200 mm/year applied in four equal treatments 2 weeks apart, timed to begin with flowering and continue through seed formation. First flowering occurred in the third year after planting. Seed production increased from the fourth through the sixth year. Optimal irrigation for seed production was calculated as 140 mm/year.