ABOUT THE COLLECTIONS

Welcome to the Rangeland Ecology & Management archives. The journal Rangeland Ecology & Management (RE&M; v58, 2005-present) is the successor to the Journal of Range Management (JRM; v. 1-57, 1948-2004.) The archives provide public access, in a "rolling window" agreement with the Society for Range Management, to both titles (JRM and RE&M), from v.1 up to five years from the present year.

The most recent years of RE&M are available through membership in the Society for Range Management (SRM). Membership in SRM is a means to access current information and dialogue on rangeland management.

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Print ISSN: 0022-409x

Online ISSN: 1550-7424

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Recent Submissions

  • Autumn and spring drought periods affect vegetation on high elevation rangelands of Turkey

    Koç, A. (Society for Range Management, 2001-09-01)
    The amount and temporal distribution of precipitation received is of critical importance for regrowth and plant production on rangelands. The effects of drought in the autumn, and spring/summer, as they affected sheep fescue (Festuca ovina L.) dominated vegetation in Eastern Anatolia, Turkey, were examined between 1996 and 1998. Artificial drought was created using polyethylene rain-out shelters. The experiment was a randomized complete block design with 3 replications with a split-plot arrangement of treatments. Main plots included 2 autumn treatments: imposed artificial autumn-drought or a 40 mm of additional water plus rain. Sub-plots contained 4 treatments: artificial drought in May, June, July, or full spring rainfall. The number of reproductive shoots, aboveground biomass production, protein content, protein yield, canopy coverage and botanical composition were determined. Reproductive shoot numbers were reduced from 617 to 31 m(-2) when plants entered winter without autumn regrowth as a result of autumn-drought. Plots subjected to drought in the autumn had aboveground biomass of 424 kg ha(-1). Protein content of forage, crude protein yield and water use efficiency (WUE) were 11.6%, 49 kg ha(-1) and 1.5, respectively. These were compared with 1,038 kg ha(-1), 9.6%, 99 kg ha(-1), and 2.4, respectively, for plots received normal autumn precipitation in addition to 40 mm of additional water. Aboveground biomass production increased as short-term drought in spring was delayed but WUE was decreased. Autumn-drought had no effect on the proportion of grasses, but reduced legumes and resulted in an increase in other species. Spring/summer-drought had no effect on legumes but, as the onset of drought was delayed, grasses decreased and other species increased in composition. Autumn-drought reduced canopy coverage from 34.7% to 23.8% but spring drought had a negligible effect. Results indicated that autumn precipitation was crucial for productivity of these high elevation rangelands.
  • Effect of fire on perennial grasses in central semiarid Argentina

    Pelaez, D. V.; Boo, R. M.; Mayor, M. D.; Elia, O. R. (Society for Range Management, 2001-09-01)
    Fire is a key factor in the temperate semiarid region of central Argentina. The objectives of this work were to evaluate the effect of different fire intensities applied during different seasons under field conditions on the mortality of Piptochaetium napostaense (Speg.) Hack., Stipa tenuis Phil., and Stipa gynerioides Phil., 3 of the dominant grasses within the region and to determine their thermal death points in the laboratory. Ten plants of each species were exposed to low fire intensity (300-400 degrees C), high fire intensity (500-600 degrees C), and no fire (control) in April and December 1994, May 1995, and January 1996. Fire treatments were applied with a portable propane plant burner. The thermal death point was determined (during fall and spring) using the Wright's technique. Although mortality with high fire intensity was always higher than mortality with low fire intensity for all species, differences were not significant (p > 0.05). Pooling both treatments, the highest (p < 0.05) average mortality for P. napostaense (55%) and S. tenuis (85%) was observed after the May burn. Average mortality for S. gynerioides was similar (p > 0.05) for all burning dates. Only after the May burn, was average mortality of P. napostaense and S. tenuis higher (p < 0.05) than average mortality of S. gynerioides. The thermal death point was similar in all studied species. It was 65 degrees C during the fall, and 68 degrees C during the summer. This could explain, at least in part, similar mortalities (except after the May burn) between species and the date of burning found in this study.
  • Quantifying suitable habitat of the threatened western prairie fringed orchid

    Wolken, P. M.; Sieg, C. H.; Williams, S. E. (Society for Range Management, 2001-09-01)
    Land managers need accurate and quick techniques to identify suitable habitat of species of interest. For species protected by federal or state laws, identification of suitable habitat is critical for developing a conservation strategy that includes reestablishing populations and altering management to address this need. In this research, we quantified vegetative and edaphic habitat of the western prairie fringed orchid (Platanthera praeclara Sheviak and Bowles), a federally listed threatened plant. Lowlands (swales) that supported orchids in our southeastern North Dakota study area were characterized as having a higher soil moisture content within the top 10 cm, when compared to swales devoid of orchids. The vegetative composition of orchid-supporting swales reflected this higher moisture content. These data were then used in developing a logistic regression model to differentiate suitable habitat. The model correctly classified 84% of 38 swales as either orchid-supporting or non-orchid-supporting using 4 variables: percent canopy cover of Baltic rush (Juncus balticus Willd.) and hedge-nettle (Stachys palustris L.), soluble soil magnesium and August surface soil moisture. Land managers can use this model to rapidly assess the suitability of a site in this ecoregion for the orchid. By collecting data on the cover of just Baltic rush, which would take about 45 minutes, and entering it in the equation, a land manager could correctly classify 66% of the orchid swales as either suitable or unsuitable as orchid habitat. This approach, because it incorporates quantitative data and allows managers to rapidly and accurately identify suitable habitats, shows promise for other plant species.
  • Redberry juniper canopy cover dynamics on western Texas rangelands

    Ueckert, D. N.; Phillips, R. A.; Petersen, J. L.; Wu, X. B.; Waldron, D. F. (Society for Range Management, 2001-09-01)
    Knowledge of the rate woody plant canopy cover increases is essential for understanding the ecology of rangeland plant communities, determining the economic feasibility of brush management practices, and for scheduling initial and maintenance control practices. We determined rates of change in redberry juniper (Juniperus pinchotii Sudw.) canopy cover from the mid 1950s through the late 1990s at 5 locations in western Texas on rangeland that had been chained or grubbed for juniper control and on adjacent untreated areas. Juniper cover was estimated from aerial photographs by the line intercept method using a 10-X monocular lens with a vernier. Juniper cover increased at 0.35 +/- 0.06 percentage units year(-1) on untreated sites and at 1.01 +/- 0.07 percentage units year(-1) following chaining or grubbing. Juniper cover returned to pre-treatment levels in an average of 20 years (range 11 to 25) following chaining or grubbing. Herbage production on untreated rangeland was predicted to decline slowly (2.4 to 5.0 kg ha(-1) year(-1)) as juniper cover increased from 6 to 14% and rapidly (> 8 kg ha(-1) year(-1)) as juniper cover increased from 30 to 38%. Herbage production was predicted to decline at a constantly increasing rate following mechanical control of juniper, from < 2 kg ha(-1) year(-1) in year 1 to 23 kg ha(-1) year(-1) in year 29. Potential additional livestock carrying capacity due to juniper control would be under estimated by more than 40%, assuming forage production without treatment remained constant during the entire planning horizon of an economic analysis. To avoid significant reductions in livestock carrying capacity, redberry juniper control should be implemented before its canopy cover exceeds about 20%.
  • Bitterbrush and cheatgrass quality on 3 southwest Idaho winter ranges

    Bishop, C. J.; Garton, E. O.; Unsworth, J. W. (Society for Range Management, 2001-09-01)
    Nutritional stress is an important mortality factor for wintering mule deer (Odocoileus hemionus hemionus Rafinesque), particularly fawns. The rate at which fawns utilize existing fat stores is at least partially dependent upon the quality of available forage during winter. Although numerous studies have determined the nutritive value of various forage species, more research is needed to determine whether individual forage species vary in quality across the landscape. We determined whether differences existed in the nutritional quality of antelope bitterbrush (Purshia tridentata [Pursh] DC.) and cheatgrass brome (Bromus tectorum L.) among 3 winter ranges and 6 habitats within the winter ranges. In vitro dry matter digestibility (IVDMD) of bitterbrush varied among winter ranges in 1996 and 1997 (P < 0.001). The highest mean IVDMD measured on a winter range was 29.8% (n = 36, SD = 3.87) in 1997 while the lowest was 15.2% (n = 38, SD = 4.42) in 1996. Bitterbrush crude protein (CP) was different among habitats in 1997 (P = 0.005), with mean CP values ranging from 7.0% (n = 19, SD = 0.73) to 8.0% (n = 13, SD = 0.70). The length and diameter of available bitterbrush leaders varied within and among winter ranges because of differential utilization. Bitterbrush IVDMD and CP varied in relation to the mean diameter of leaders obtained from each random sampling site (P 0.001). The quality of bitterbrush decreased as browse intensity increased. Cheatgrass IVDMD was different between winter ranges (P < 0.001) in 1996, with mean values ranging from 65.8% (n = 36, SD = 4.34) to 69.6% (n = 36, SD = 3.83). Site-specific variation should be considered when evaluating the nutritional quality of mule deer habitat, at least during winter when species diversity in deer diets is limited.
  • Point sampling for leaf area index in sagebrush steppe communities

    Clark, P. E.; Seyfried, M. S. (Society for Range Management, 2001-09-01)
    Although point sampling has been used for more than 30 years to quantify leaf area index (LAI), this field technique has not been rigorously evaluated in sagebrush steppe plant communities. Leaf area index estimates obtained using different sampling pin inclinations or combinations of pin inclinations were evaluated in Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle and Young), low sagebrush (Artemisia arbuscula Nutt.), and mountain big sagebrush (Artemisia tridentata Nutt. ssp. vaseyana [Rydb.] Beetle) communities within the Reynolds Creek Experimental Watershed near Boise, Ida. Leaf area index values determined by clipping and processing green foliage through a leaf area meter were used as evaluation standards. Pins inclined at 13 degrees from the horizontal, used alone or in combination with pins of 52 degrees and/or 90 degrees inclinations, performed poorly for estimating LAI in the Wyoming big sagebrush and low sagebrush communities. Estimating total LAI with either the combination of 52 degrees and 90 degrees angle pins or with 52 degrees or 90 degrees pins alone explained at least 96% of the variability in LAI standard values from the Wyoming big sagebrush and mountain big sagebrush communities. Using 52 degrees angle pins alone produced model fits similar to those obtained when the combination of 52 degrees and 90 degrees angle pins were used to estimate shrub, graminoid, and forb LAI across all 3 communities (P > 0.1). Collecting point data using 52 degrees angle pins often provided better or similar model fits with LAI standards compared to other pin angles but using 90 degrees angle pins offers a better compromise between practicality, efficiency, and accuracy.
  • Evaluation of 3 techniques for determining diet composition

    Henley, S. R.; Smith, D. G.; Raats, J. G. (Society for Range Management, 2001-09-01)
    A comparative study was made of 3 techniques applied to the study of herbivore diet selection, namely direct observation, faecal analysis and the recently developed remote control oesophageal fistula valve, using 3 animals over 4 study days. Direct observation showed a relatively high level of precision with respect to the woody forage class but a poor measurement of the grass class. The ratios of grass to dicot were similar in the diets determined by direct observation and valve fistulation, but faecal analysis over-emphasised dicots relative to the other techniques. The greatest overlap in estimated diet was between faecal analysis and valve fistulation. Overall the valve fistulation technique was considered superior to the other 2 techniques because it provided reliable estimates of diet composition that could be readily equated to range conditions at the time of ingestion.
  • Seed recovery and germination of reseeded species fed to cattle

    Doucette, K. M.; Wittenberg, K. M.; McCaughey, W. P. (Society for Range Management, 2001-09-01)
    Cattle have the potential to act as a low cost alternative for seed dissemination of valuable native species. Data collected from this trial was used to compare seed recovery, rate of passage and viability following ingestion and excretion of 7 plant species. Woods rose (Rosa woodsii Lindl.), snowberry (Symphoricarpos albus L.), purple prairie clover (Petalostemom purpureum Vent.), birdsfoot trefoil (Lotus corniculatus L.), western wheatgrass (Pascopyrom smithii Rydb A. Love, formerly known as Agropyron smithii Rydb.), green needlegrass (Nassella viridula Trin.), and yellow coneflower (Ratibida columnifera Nutt.) seed was used in the study. Two steers were fed a seed-free diet consisting of fresh cut vegetative Kentucky bluegrass (Poa pratensis L.)-alfalfa (Medicago sativa L.) forage. Following a 13 day adjustment period to the diet, steers were fed a single dose of a known number of seeds, and total feces collection was conducted for 168 hours post dosing. Fecal sub-samples were subjected to a stacked screen washing procedure for seed recovery and analysis. Seeds from both pre- and post-ingestion were tested for hard seededness, firm ungerminated seed, and germination. Seed recovery varied between seed types, ranging from 5.9% of total ingested seed for western wheatgrass, to 86.3% for Woods rose. Excretion patterns for ingested seed varied between seed types, with 50% of excreted seed being recovered between 30 to 54 hours post-dosing. Seed ingestion and passage through the digestive tract reduced viability. Cattle dissemination of viable seeds (as a % of ingested) such as Woods rose (77.4) and snowberry (69.3), would be a feasible method of delivering large numbers of viable seeds onto selected areas. Dissemination of birdsfoot trefoil (17.5), green needlegrass (11.9), and purple prairie clover (7.2), yellow coneflower (3.8), and western wheatgrass (1.3), using cattle would be less efficient, implementation should be based on seed access and cost.
  • Hydrologic responses of a montane riparian ecosystem following cattle use

    Flenniken, M.; McEldowney, R. R.; Leininger, W. C.; Frasier, G. W.; Trlica, M. J. (Society for Range Management, 2001-09-01)
    Riparian areas link streams with their terrestrial catchments and decrease water pollution by trapping sediments from upland sources before they reach streams or lakes. Livestock grazing in riparian areas is a controversial practice. If not properly managed, cattle can cause degradation to both the riparian zone and adjacent water body. Vegetative, soil microtopographical, microchannel and hydrograph parameters were measured in a montane riparian community in northern Colorado to quantify the effects of cattle on overland flow and runoff characteristics. Treatments were cattle grazing plus trampling, cattle trampling, mowing, and a control. Water was applied to plots (3 m x 10 m) at a rate of 100 mm hr(-1) using a rainfall simulator. Concurrently, overland flow was introduced at the upper end of the plots at an equivalent rate of 25 mm hr(-1). A high intensity-short duration grazing treatment was used for the cattle-treated plots. Reduction in vegetation stem density and aboveground biomass by cattle decreased microchannel sinuosity and drainage density. Cattle-treated plots had greater flow velocities and depths in microchannels compared with mowed and control plots. Reduced stem density and aboveground biomass by grazing left fewer obstacles to divert flows, which decreased microchannel sinuosity and drainage density. Flows were concentrated into fewer microchannels with deeper flows. Microchannel characteristics were not significant factors affecting total runoff. Stem density and rainfall intensity were the most important factors in predicting runoff characteristics and total runoff. Results from this study have improved our understanding of flow and runoff processes following cattle use of a riparian ecosystem.
  • Resilience of prickly burnet to management in east Mediterranean rangelands

    Perevolotsky, A.; Ne'Eman, G.; Yonatan, R.; Henkin, Z. (Society for Range Management, 2001-09-01)
    Large areas of rangelands in the east Mediterranean Basin are dominated by dense cover of the unpalatable, dwarf shrub prickly burnet (Sarcopoterium spinosum (L.) Spach.). This study examined the effectiveness of various shrub control treatments (mechanical removal, chemical/2,4-D control, prescribed burning), combined with NPK fertilization, to reduce shrub cover and encourage the growth of palatable herbaceous vegetation. Chemical control was the most effective treatment, reducing prickly burnet cover to 40% of the initial level 2 years after treatment. Mechanical removal maintained shrub cover at 60% of the initial level, whereas the effect of fire was not detectable after 2 years. Annual and perennial herbaceous vegetation cover was negatively correlated with shrub cover. Fertilization had no effect on the cover of the vegetative components, but increased biomass on the herbaceous patches by 25-240%, depending on the treatment. Our results demonstrate the exceptionally high resilience of prickly burnet growing on chalk substrate to disturbance or attempted eradication, thus rendering most of the tested management options highly ineffective. Effective improvement of rangeland dominated by prickly burnet requires, most probably, a combined treatment including removal of mature shrubs, suppressing their recovery, and stimulating the competing grass component.
  • Economics of managing mesquite in north Texas: A sensitivity analysis

    Teague, W. R.; Ansley, R. J.; Kreuter, U. P.; Pinchak, W. E.; McGrann, J. M. (Society for Range Management, 2001-09-01)
    This paper presents a comparative simulation analysis of the economics of prescribed fire and aerially applied root-killing herbicide treatment as methods for maintaining livestock productivity on rangeland in the Texas Rolling Plains. A "no-treatment" scenario is used as the base for comparison. In almost all the simulated scenarios both herbicide application and prescribed burning were economically feasible since net present values were > 0 and benefit/cost ratios were > 1. However, the net present values for prescribed fire were much higher that those for the herbicide treatment even with a lower increase in carrying capacity with burning. The cost of herbicide would have to be less than half the current cost of 57 ha(-1) before it would be economically competitive with fire in controlling mesquite. If cattle numbers were not increased after treating brush, burning had an even greater net present value and benefit/cost ratio advantage over herbicide treatment than if cow numbers were increased after treatment. Even if fences have to be constructed to implement adequate deferment for burning, the net present value and benefit/cost ratios of the fire option were higher than those for herbicide scenarios. This analysis indicates that there is an economic advantage to using fire wherever possible, and use of herbicides is restricted to those instances when fine fuel amount is < 1,700 kg ha(-1) yr(-1) when fire is not a viable option. The analyses indicate the economic response is most sensitive to the treatment effect on wildlife income.
  • Grassland birds associated with agricultural riparian practices in southwestern Wisconsin

    Renfrew, R. B.; Ribic, C. A. (Society for Range Management, 2001-09-01)
    Rotational grazing has been proposed as a Best Management Practice (BMP) for minimizing runoff in Wisconsin agricultural riparian areas. The influence of this land management practice on grassland birds has not been evaluated in relation to more traditional agricultural land management systems in Midwestern riparian areas. This study compared the grassland bird community in riparian areas in Wisconsin that were rotationally grazed to 2 common land use practices along streams in Wisconsin: continuously grazed pastures and rowcrop fields with 10-m-wide ungrazed buffer strips located along the stream. We calculated total number of birds, the Berger-Parker Index of Dominance, and number of birds ha(-1) for each site. Vegetation variables used were height-density, litter depth, and percent bare ground. Bird species richness, species dominance, and density did not differ among land use types. In contrast, grassland bird species of management concern [Savannah Sparrow (Passerculus sandwichensis Gmelin), Eastern Meadowlark (Sturnella magna L.), and Bobolink (Dolichonyx oryzivorus L.)] were found on continuous and rotational pastures but very rarely or never occurred on buffer strips. Contrary to previous research, however, rotationally grazed pastures did not support more of these species than continuously grazed pastures. Bird density was related to vegetation structure, with higher densities found on sites with deeper litter. Within the pasture land use types, there were no consistent differences between species richness and density near the stream (10 m) and away (10 m).
  • Characterization and habitat preferences by white-tailed deer in Mexico

    Bello, J.; Gallina, S.; Equihua, M. (Society for Range Management, 2001-09-01)
    We analyzed the habitat preferences of white-tailed deer in a 1,000 ha area in an arid region of northeastern Mexico where drinking water is abundant throughout the year (via 33 water troughs). Seven habitat types in the study area were identified and characterized. Within each habitat, feeding, searching, and bedding activities were evaluated during the reproduction, postreproduction and fawning seasons of the annual deer cycle. The Acacia-Celtis habitat provided the greatest amount of hiding and thermal cover and edible food. The Prosopis habitat also provided significant hiding and thermal cover. Hilaria and Opuntia were the most open habitats. Habitat preferences, evaluated by radiotracking 14 deer over a period of 2 years, varied between sexes and years (P << 0.00001), but not among seasons (P > 0.05). Male deer preferred open habitats, while females preferred more densely covered ones. Males and females avoided Prosopis during 1996. Both sexes distributed the 3 activities more evenly during 1996 than during 1995. In 1995, females preferred Flourensia and Acacia-Celtis habitats for all activities, and during 1996 males preferred Hilaria and Leucophyllum. Between year changes in precipitation could explain the observed variability: during 1995 rainfall was 136 mm, as compared to 276 mm in 1996. Requirements for cover increased markedly in 1995 due to high predation and extremely dry conditions. Overall, our study shows that under good weather conditions, habitat preferences are best explained by variables associated with food availability, while thermal cover is more important under harsh weather conditions, even when drinking water is abundant.
  • Spatial modeling of rangeland potential vegetation environments

    Jensen, M. E.; Dibenedetto, J. P.; Barber, J. A.; Montagne, C.; Bourgeron, P. S. (Society for Range Management, 2001-09-01)
    Potential vegetation environments (e.g., habitat types, range sites, ecological sites) are important to land managers because they provide a conceptual basis for the description of resource potentials and ecological integrity. Efficient use of potential vegetation classifications in regional or subregional scale assessments of ecosystem health has been limited to date, however, because traditional ecological unit mapping procedures often treat such classifications as ancillary information in the map unit description. Accordingly, it is difficult, if not impossible, to describe the precise location, patch size, and spatial arrangement of potential vegetation environments from most traditional ecological unit maps. Recent advances in remote sensing, geographic information systems (GIS), terrain modeling, and climate interpolation facilitate the direct mapping of potential vegetation through a predictive process based on gradient analysis and ecological niche theory. In this paper, we describe how a predictive vegetation mapping process was used to develop a 30 m raster-based map of 4 grassland, 5 shrubland, and 6 woodland habitat types across the Little Missouri National Grasslands, North Dakota. Discriminant analysis was used in developing this potential vegetation map based on 6 primary geographic information system themes. Geoclimatic subsections and remotely sensed vegetation lifeform maps were used in predictive model stratification. Terrain indices, LANDSAT satellite imagery, and interpolated climate information were used as independent (predictor) variables in model construction. A total of 616 field plots with known habitat type membership were used as dependent variables and assessed by a jackknife discriminant analysis procedure. Accuracy values of our map ranged from 54 to 77% in grasslands, 62 to 100% in shrublands, and 70 to 100% in woodlands dependent on geoclimatic subsection setting. Techniques are also described for generalizing the 30 m pixel resolution habitat type map to appropriate ecological unit maps (e.g., landtype associations) for use in ecosystem health assessments and land use planning.
  • Community characteristics of old-growth western juniper woodlands

    Waichler, W. S.; Miller, R. F.; Doescher, P. S. (Society for Range Management, 2001-09-01)
    While considerable attention has been given to the areal expansion of juniper (Juniperus sp.) in the western United States, the presence and ecological significance of old-growth juniper communities has gone largely unnoted. Increased recognition of these communities has prompted questions about how to recognize old-growth, community structure, ecological importance, and appropriate management. As an initial analysis of old-growth western juniper woodlands (Juniperus occidentalis Hook var. occidentalis Vasek) in central Oregon, this study investigated old-growth community structure on eolian-sand derived soils. These woodlands represent the most extensive old-growth western juniper woodlands throughout its range. Nine study plots were established at 7 sites. Within each plot, densities and physical attributes of all live trees and large standing and fallen woody detritus were recorded. Additional measurements for live trees included canopy cover, apparent age class (pre- or postsettlement), and a sampling of tree ages. Aging of trees older than 250 years was complicated by extensive heartwood rot. Shrub density and cover were measured by species. Understory cover was measured by species and functional type. Bare ground, rock, juniper litter, other litter, moss, and cryptogamic crust cover were also measured. Plant cover ranged from 11 to 33% for trees, 0 to 10% for shrubs, 3 to 12% for perennial grasses, 1 to 2% for forbs, and from 0 to 0.1% for annual grasses. The woodlands contained at least 80 trees ha(-1) aged over 200 years. Correlations between tree parameters and understory structure and composition were generally poor. Differences in plant composition among these stands was primarily attributed to elevation, slope, and percent sand content. Structural characteristics that distinguished old-growth stands from younger stands included tree growth form, presence of standing and dead large woody debris, lichen on dead branches, and a relatively open canopy. Results provide a preliminary basis for identifying old-growth Juniperus occidentalis stands, as a prelude to the development of management plans and further research into the functional characteristics of the systems. A definition of old-growth juniper woodlands is presented.
  • Principles and practices for managing rangeland invasive plants

    Masters, R. A.; Sheley, R. L. (Society for Range Management, 2001-09-01)
    Invasive plants reduce the capacity of ecosystems to provide goods and services required by society, alter ecological processes, and can displace desirable species. They can reduce wildlife habitat quality, riparian area integrity, rangeland economic value, and enterprise net returns. The invasion process is regulated by characteristics of the invading plant and the community being invaded. The presence and spread of invasive plants is often symptomatic of underlying management problems that must be corrected before acceptable, long-term rangeland improvement can be achieved. Disturbance appears to be important early in the invasion process because it creates vacant niches that alien plants can occupy. Control of invasive plants may only open niches for establishment of other undesirable plants unless desirable plants are present to fill the vacated niches. In many instances, rangelands have deteriorated to the point that desirable species are either not present, or in such low abundance that plant community recovery is slow or will not occur without revegetation after invasive plants are controlled. Integrated weed management employs the planned, sequential use of multiple tactics (e.g. chemical, biological, cultural, and mechanical control measures) to improve ecosystem function (energy flow and nutrient cycling) and maintain invasive plant damage below economic levels, and emphasizes managing rangeland ecosystem functions to meet objectives rather than emphasizing a particular weed or control method. Sustainable, integrated invasive plant management strategies require assessing plant impacts, understanding and managing the processes influencing invasion, knowledge of invasive plant biology and ecology, and are based on ecological principles. Invasive plant management programs must be compatible with and integrated into overall rangeland resource management objectives and plans. Because of the complexity of managing invasive plants, it is imperative that relevant ecological and economic information be synthesized into user-friendly decision support systems.