2002-07-08_GENERAL DOCUMENTS - M2002004 (3)

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Table 1. Estimates of costs per Wyoming big sagebrush seedling and values in ( ) represent the cost per hectare to establish 2000 seedlings. Sagebrush sdlgs m 2 1.32' 2.36 2.48 4.43 $100 meet the shrub standard. If we were to use the present day estimated costs of transplantation (Kleinman and Richmond 2000) with 100% survival, direct seeding would only cost 2.4% of the cost of transplantation. The authors realize that seed availability and cost may become a significant consideration in meeting the shrub standard on mined lands in Wyoming where Wyoming big sagebrush is the required species in most situations, but we believe that economics will remain the driving force behind the decisions made by the industry and regulatory personnel in determining the option used in establishing this shrub on mined lands. Seed use efficiency might be much better with nursery grown seedlings, but costs will likely dictate the use of direct seeding and over -ride the seed - use - efficiency concerns/considerations. Demand for native shrub seed will result in improved seed collection and processing and improved cultural practices for orchard production of these species. In fact, local producers have recently begun producing Wyoming big sagebrush under seed orchard conditions (Richard Dunne, personal communication, 1999) to more consistently meet the demand for good quality seed. There may be briefperiods of seed shortages but demand will greatly aid in the development of seed production and in direct seeding practices. Even considering the vast differences in cost between direct seeding vs transplantation, there may be small, site specific areas and instances where the use of nursery grown transplantation might be used to meet a very specialized objective. But it is difficult to visualize transplantation being used to meet the shrub standard in general reclamation practices considering the several 44 Seed Cost kg' PLS $200 Survival Rate Cost seedling' (cost ha'') $300 $0.015 $0.008 $0.030 $0.019 $0.045 $0.025 ($30) ($17) ($60) ($34) ($90) ($51) $0.016 $0.009 $0.032 $0.018 $0.048 $0.027 ($32) ($18) ($64) ($36) ($96) ($54) ' These sagebrush seedling densities represent 33 and 59% survival of the densities measured (4.0 seedlings m by Fortier (2000) at the sagebrush seeding rate of 2 kg PLS ha'' and 8 kg PLS ha'' grass seeding rate. b These sagebrush seedling densities (seedlings m) represent 33 and 59% survival of the density (7.5 seedlings m) measured by Fortier (2000) at the sagebrush seeding rate of 4 kg PLS ha' and 8 kg PLS ha' grass seeding rate. Cost per hectare values are rounded to the nearest full dollar. magnitude difference in costs which will not be easily overcome even with major advances in transplantation technology. Summary Much research has been accomplished within the last three decades in attempting to better understand the ecology of Wyoming big sagebrush establishment on mined lands. The interest in this subject was even further raised when the Wyoming Department of Environmental Quality, Land Quality Division established shrub density re- establishment requirements for lands affected after August 6, 1996. This standard requires that a density of 1 shrub m' be re- established on 20% of the land area affected and that 50% of the density must be composed of the predominant shrub prior to disturbance. Since Wyoming big sagebrush is widely distributed over Wyoming, that means that it will likely be a major component of the pre -mine plant community and therefore must be re- established on 20% of all coal mined lands to meet the shrub standard. In fact, all lands classified as "grazing/wildlife habitat" must have a shrub component on the other 80% of the reclaimed land, but no specific density is required. Much recent research has been done to better understand the seedbed ecology and seed ecology to enhance establishment of this species from direct seedings. This research has resulted in a better understanding of the role of mulches, topsoil quality, competition, arbuscular mycorrhiza, and seed viability and how these factors can be managed to greatly improve seedling establishment through direct seeding. At today's technology and economics direct seeding is