Effects of Age, Burial, and Region on Germination and Viability of Halogeton Seed'

The longevity of brown and black forms of seed of haloge- ton (Halogeton glomeratats (M. Bieb.) C. A. Mey.), buried at four depths, was determined for a 10-year period in Nevada, Idaho, Utah, and Washington. The black formi of seed had almost 100% field germination at all depths by the end of the first year and had completely germinated or was nonviable by the end of the second. Brown seed on the soil surface began field germination the first year at all locations and had germinated or become nonviable at the end of 6 years. Burial at 1, 3, and 6 inches delayed the peak of viability and tended to increase longevity of brown seed. Germina- tion was less than 0.5% at the end of 10 years, and viability was near zero under both field and laboratory conditions. Seed germninated and lost viability most rapidly in Washington, the location where most favorable winter conditions for germination occurred.