Excerpt from Response of Grass Species to Tree Harvesting in Singleleaf Pinyon-Utah Juniper Stands These are estimates from the mean of the two closest official weather stations in the same vegetation type (reese River Valley and Austin). About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Understory species associations and their association with tree species were examined on three intensively studied stands. We studied the chronosequence of understory species associated with different aged singleleaf pinyon (Pinus monophylla Torr. and Frem.) trees. Mid- to late pinyon-juniper understory succession was found to be more spatial than floristic in nature. Plants of the same species but occurring on different soil microsites responded differently to increasing tree competition. Succession was a plant by plant process rather than a linear replacement series of species at the population level. Phytosociological changes were documented following tree harvesting on 15 widely separated singleleaf pinyon-Utah juniper (Juniperous osteosperma [Torr.] Little) stands. Pre- and post harvest plant assemblages from the same site appeared in the same phytosociological groupings 80% of the time as defined by discriminate analysis. We suggest initial post harvest response was short term cyclic rather than successional and therefore more predictable. Post harvest seed rain suggested understory species have increased reproductive potential following tree harvest and can rapidly reoccupy disturbed sites. Survival strategies of individual species determined the quantitative character of seed rain Seed rain and subsequent seedling establishment were not the primary causes of increased understory cover following tree harvest. Remnant plants provided the initial cover increase. Post harvest cover rapidly increased for two years on the three intensively studied sites, but rate of increase declined during the following two year period. Soil microsites associated with the tree canopy produced greater grass yields than soils in the interspace between trees. Percent nitrogen and phosphorus increased in most grass species following tree harvest. Because of increased soil nutrient concentrations under the tree canopy we anticipated higher nutrient level in associated grass plants, but were unable to demonstrate this difference because of the dilution effects from increased yields. Soil nutrients were concentrated under the tree crown but were not distributed similarly with depth. Mineralizable-N, PO4, Zn, Mn, Cu, and Fe, accumulated in surface horizons. Total soluble salts, Ca, Mg, Na, and K accumulated in subsurface horizons. Nutrient enrichment in soils under the canopy was suggested to confer a competitive advantage to the tree species.