Western Juniper Field Guide: Asking the Right Questions to Select Appropriate Management Actions

Strong evidence indicates that western juniper has significantly expanded its range since the late 1800s by encroaching into landscapes once dominated by shrubs and herbaceous vegetation (fig. 1). Woodland expansion affects soil resources, plant community structure and composition, water, nutrient and fire cycles, forage production, wildlife habitat, and biodiversity. Goals of juniper management include an attempt to restore ecosystem function and a more balanced plant community that includes shrubs, grasses, and forbs, and to increase ecosystem resilience to disturbances. Developing a management strategy can be a difficult task due to uncertainty about how vegetation, soils, hydrologic function, and wildlife will respond to treatments. When developing a management strategy, the first and possibly most important step towards success is asking the right questions. Identifying the attributes of the area to be treated and selecting the right treatments to be applied are of utmost importance. One must ask questions addressing the kind of site (that is, potential natural vegetation, soils, etc.), the current state of the site (that is, successional, hydrologic, etc.), what components need to be restored, how the management unit fits in with the overall landscape mosaic, and the long-term goals and objectives for the area or region. Keep in mind sagebrush-steppe vegetation is dynamic and management strategies must take into account multi-decade time frames. This guide provides a set of tools that will help field biologists, land managers, and private landowners conduct rapid qualitative field assessments that address the kind of site and its current state. These tools include a list of questions to be addressed and a series of photographs, keys, tables, and figures to help evaluate a site. Conducting this assessment will help prioritize sites to be treated, select the best treatment, and predict outcomes. Success of a juniper management program may be greatly enhanced if an interdisciplinary team of local managers and resource specialists, who are experienced with vegetation, fuels, soils, hydrology, wildlife, and economic and sociological aspects of the local resource, use this guide to aid their decision-making

Endocytotic formation of vesicles and other membranous structures induced by Ca2+ and axolemmal injury

Vesicles and/or other membranous structures that form after axolemmal damage have recently been shown to repair (seal) the axolemma of various nerve axons. To determine the origin of such membranous structures, (1) we internally dialyzed isolated intact squid giant axons (GAs) and showed that elevation of intracellular Ca21 .100 uM produced membranous structures similar to those in axons transected in Ca21-containing physiological saline; (2) we exposed GA axoplasm to Ca21- containing salines and observed that membranous structures did not form after removing the axolemma and glial sheath but did form in severed GAs after .99% of their axoplasm was removed by internal perfusion; (3) we examined transected GAs and crayfish medial giant axons (MGAs) with time-lapse confocal fluorescence microscopy and showed that many injuryinduced vesicles formed by endocytosis of the axolemma; (4) we examined the cut ends of GAs and MGAs with electron microscopy and showed that most membranous structures were single-walled at short (5–15 min) post-transection times, whereas more were double- and multi-walled and of probable glial origin after longer (30–150 min) post-transection times; and (5) we examined differential interference contrast and confocal images and showed that large and small lesions evoked similar injury responses in which barriers to dye diffusion formed amid an accumulation of vesicles and other membranous structures. These and other data suggest that Ca21 inflow at large or small axolemmal lesions induces various membranous structures (including endocytotic vesicles) of glial or axonal origin to form, accumulate, and interact with each other, preformed vesicles, and/or the axolemma to repair the axolemmal damage.This work was supported by grants from National Institutes of Health (NIH; NS31256) and the State of Texas (Advanced Technology 3658-446).Neuroscienc

Western juniper : its impact and management in Oregon rangelands

This publication acquaints you with the biology and ecology of western juniper and how the tree affects the landscapes it occupies.Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo

Preconceptional Folate Supplementation and the Risk of Spontaneous Preterm Birth: A Cohort Study

In an analysis of a cohort of pregnant women, Radek Bukowski and colleagues describe an association between taking folic acid supplements and a reduction in the risk of preterm birth

A Field Stereophotographic Technique for Range Vegetation Analysis

Color negative film used in a camera with a lens providing a good depth of field at short focal distances has produced stereo color prints that permit accurate identification and measurement of range vegetation with a pocket stereoscope. This system can overcome many of the problems of inventorying a range.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Germination of green and gray rubber rabbitbrush and their establishment on coal mined land

The objectives of this study were to: (1) determine the effects of temperature and water stress on germination, and; (2) evaluate effects of seeding date on emergence and survival of green and gray rubber rabbitbrush (Chrysothamnus nauseosus (Pallas) Britt. subsp. graveolens (Nutt.) Piper. and Chrysothamnus nauseosus (Pallas) Britt. subsp. nauseosus (Nutt.) Piper.). Seeds of both shrubs were incubated at 10, 20, and 30 degrees C in a gradient of osmotic potentials ranging from 0.0 to -1.5 MPa. Seedings were also made in the field on seeding dates over a period of 3 years. Total germination and germination rate declined as temperatures and osmotic potentials decreased; they were highest for both shrubs at 20 and 30 degrees C and lowest at 10 degrees C. Under field conditions seedling populations were limited by low emergence and survival relative to viable seed planted. Emergence and survival of seedlings were highest in an exceptionally wet year, declining in subsequent years that were drier. Emergence ranged from 0 to 6.9% and 0 to 7.1% and survival of emerged seedlings ranged from 6.6 to 55% and 0 to 60% for green and gray rubber rabbitbrush, respectively. Survival of green rubber rabbitbrush was highest from mid-spring plantings, but no distinctively favorable seeding date was found for gray rubber rabbitbrush. Results suggest that seeds of these shrubs should be planted prior to or during periods when seedbed temperatures are in the 20 to 30 degrees C range and soil moisture is expected near its seasonal high.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

A Test of Stereophotographic Sampling in Grasslands

Color stereophotography was used to sample a grassland vegetation type for species presence and for cover. Square foot estimate plots were used as a check. Three-Pee sample selection was also tested. Species identification proved difficult in dry, weathered vegetation. Cover estimates were lower for single stemmed and linear leaved weathered plants in the stereophotographic sample than in the square foot field estimate. Three-Pee sampling gave similar results to complete estimates.This material was digitized as part of a cooperative project between the Society for Range Management and the University of Arizona Libraries.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202

Use of degree-days in multiple-temperature experiments

This research compared results from germination and growth when the experiment duration was chronologically set or based on degree-days. Seeds of smooth brome (Bromus inermis Leyss.), plains rough fescue (Festuca altaica Trin. subsp. hallii (Vasey) Harms), prairie coneflower (Ratibida columnifera (Nutt.) Woot. and Standl.), and silver sagebrush (Artemisia cana Pursh.) were germinated at 5, 10, 15, 20, and 25 degrees C for 28 days or 400 degree-days (Base temperature = 0 degrees C). Root and shoot weights of seedlings of these species were compared at 5, 10, 15, 20, 25 and 30 degrees C after growing them 20 days or 200 degree-days. With the exception of prairie coneflower, optimal temperatures for germination were 2 to 4 degrees C lower when incubated 400 degree-days compared to 28 days. Total germination for prairie coneflower was not significantly different (P = 0.454) at 28 days or 400 degree-days. Interacting effects of the duration of experiments and temperature significantly (P less than or equal to 0.001) influenced root and shoot weight of all species. Except for shoot weight of smooth brome, predicted optimum temperatures for root and shoot growth were 7 to 21 degrees C lower at 200 degree-days than 20 days. These experiments illustrate that results from germination and growth studies can vary substantially depending on whether chronological time or degree-days are used as the end point. Thus, ecological interpretations or management recommendations can be quite different. Degree-days may be more meaningful than chronological units for germination and growth studies because they integrate time and temperature. The use of degree-days as an end point for experiments rather than chronological time deserves further consideration by researchers.The Journal of Range Management archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform August 202