2002-07-08_GENERAL DOCUMENTS - M2002004 (4)

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processing would result in an adequate quantity of naked seed without the need for further pericarp removal. As an extension to the previous study, Booth et al. (1998) in Wyoming Big Sagebrush Seed Production from Mined Lands and Adjacent Unmined Rangelands, evaluated big sagebrush seed production from reclaimed coal mine lands and undisturbed, native ground. This study was done at the Dave Johnson Coal Mine in central Wyoming from July 1995 through October 1998. Big sagebrush plants observed ranged in age from 10 to 20 years. They found the number of seed stalks per plant, seed quantities, and seed weights were greater from plants on reclaimed mine land than from companion plants on adjacent undisturbed sites. Some plants had been fenced to observe the effects of wildlife browsing. It was observed the unfenced plants produced lighter and drier seeds than the plants that were fenced. It was also observed, unexpectedly, that the fences apparently provided some environmental modification comparable to the effects of mulch and wind protection treatments applied as part of the study. Soil moisture conditions varied considerably from year to year. However, when averaged across all variables, soil moistures on reclaimed and mulched native sites was higher than on no -mulch reclaimed and no -mulch undisturbed sites. In the study Strategies for Establishment of Big Sagebrush (Artemesia Tridentata ssp Wvomingensis) on Wyoming Mined Land (Schuman and Booth 1998), looked at coal mine reclamation practices and their relationships with big sagebrush establishment. They found that direct placed topsoil did not act as a seed bank for big sagebrush as compared to stockpiled topsoil. They did find, however, that direct placed topsoil consistently had higher soil moisture and greater arbuscular mycorrhizae spore counts than did stockpiled topsoil. As a result, the direct placed topsoil sites had 40% more big sagebrush seedlings than stockpiled topsoil sites the first season of establishment and from one to two orders of magnitude more the following season. Schuman and Booth (1998) looked at the differences in mycorrhizal infection between direct placed topsoil and stockpiled topsoil. In spite of a nearly 33% greater spore count in direct placed topsoil, there was no apparent difference in the number of mycorrhizal infected big sagebrush seedlings between the two soil treatments. The authors note this may be because the non - infected seedlings had already died prior to the observations. There did seem to be a positive effect of mycorrhizae on drought stress tolerance by big sagebrush seedlings. Stubble mulch and crimped straw mulch were found to provide greater big sagebrush seedling establishment than was no mulch or stubble and straw mulch together. Grass competition was further observed to have reduced big sagebrush seedling density throughout the duration of the Schuman and Booth study. A final aspect of the Strategies for Establishment of Big Sagebrush study was the relationship and effect of seeding big sagebrush with fourwing saltbush (Atriplex canescens) as a pioneer species for later big sagebrush establishment. There were no effects, either positive or negative, shown by this phase of the study. It was observed,