Treesearch

Wildcat Creek, a tributary of the Black River on the Apache-Sitgreaves National Forest is being studied to determine the impacts of cattle and elk grazing on riparian wet meadows. An intensive survey of a selected stream reach revealed a unique channel development involving an aggradation/degradation process in a pool-riffle sequence of an E-6 stream channel. Grazing and trampling impacts of elk and cattle were found to affect the process in two ways: 1) overgrazing of stream banks resulted in exposure of the soil fabric and loss during high flows, sloughing of banks, channel widening, and...

Natural regeneration and growth of coyote willow (Salix exigua Nutt. ssp. exigua) and whiplash willow (S. lasiandra Bemth. var. caudata [Nutt.] Sudw.) were monitored from 1987 to 1993 on a low-elevation eastern Oregon stream degraded by more than a century of heavy livestock grazing. Treatments were no grazing, moderate spring grazing, moderate fall grazing, and continued heavy, season-long grazing by cattle. Fresh sediments deposited by a May 1987 flood provided moist, open seedbed conditions for willow recruitment from off-site seed sources. Initial establishment of coyote willow was...

This paper describes life histories, defoliation problems and other activities of insects associated with forest tree species growing along high elevation streams and river banks. In addition, examples of insects and diseases associated with lower elevation riparian areas are given.

Studies were initiated in June, 1994 by the USDA Forest Service, Rocky Mountain Forest and Range Experiment Station to update knowledge on the distribution of the Rio Grande cutthroat trout a Forest Service Sensitive Species, and its co-occurrence with two native cypriniforms, Rio Grande sucker and Rio Grande Chub. The Rio Grande sucker IS listed as endangered by the state of Colorado. The native cutthroat was found to co-occur with the native sucker in Tusas Creek on the Carson National Forest, and in the Rio de las Vacas, American Cr. and the Rito de las Palomas on the Santa Fe National...

This paper explores the question "is there a relationship between seasonal precipitation amounts and vegetative cover at a specific site near Grants, New Mexico?" Several hypotheses will be investigated. One is that the organizing factor for vegetation response to precipitation is the amount of summer precipitation from convective thunderstorms. The variable winter precipitation (high in El Nino years and low in La Nina years) does not provide a dependable amount of moisture, and plant cover or basal areas are not well correlated with it. Alternatively, winter or annual precipitation...

In this paper, we report species composition and relative abundances of stopover migrants during spring and fall migration along the middle Rio Grande in 1994. We recorded 157 landbird species using mist-netting and survey methods at two sites on the Rio Grande, the Bosque del Apache and the Rio Grande Nature Center. A total of 6,509 birds was captured during spring and fall migrations at these sites. Of 157 species, 47% were neotropical long-distance migrants, 50% were short-distance migrants, and the remaining 3% were residents or border migrants. Comparisons of relative abundance from...

The Rio Grande currently inundates only a small portion of its riparian forests during late spring runoff. Such flood events were once responsible for the germination of cottonwoods and willows along the river, for a mosaic of wetlands mixed with different aged stands of forest, and for enhancement of decomposition and nutrient cycling. River regulation in this century has decoupled the linkage between the floodplain and the river and has led to senescence without replacement of the once dominant native cottonwoods in the Middle Rio Grande (MRG) valley. We propose that partial restoration...

The purpose of this panel was to discuss historical and current changes to the Rio Grande system, focusing on the middle Basin, and to present and review different individual, organizational, and political perspectives on the future of the system. Invitations were made to panelists based on their past and current interests and activities pertaining to restoration of the Rio Grande. Invited panelists included Honorable Senator Pete Dominici or a representative from his staff; Jeff Whitney, U.S. Fish and Wildlife Service Coordinator for the Middle Rio Grande Bosque Initiative; Brian Shields,...

Ecosystem management should be based on the fullest possible knowledge of ecological structures and processes. In prehistoric North America, the involvement of Indian populations in ecosystem processes ranged from inadvertent alteration of the distribution and abundance of species to large-scale management of landscapes. The knowledge needed to manage ecosystems today is incomplete without understanding past human involvement in ecological processes, and the adjustments of ecosystems to human components. This paper describes changes in prehistoric land use in part of the Middle Rio Grande...

The development of irrigation agriculture in historic times has profoundly impacted riparian ecosystems in the Middle Rio Grande Valley of New Mexico. A vital relationship has existed between water resources and settlement in the semi-arid Southwest since prehistoric times. Levels of technology have influenced human generated changes in the riparian ecosystems of the Middle Rio Grande Valley.