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Articles 1 - 19 of 19

Full-Text Articles in Life Sciences

Hypoxylon Mammatum Pathotoxin Responsible For Canker Formation In Quaking Aspen, Arthur L. Schipper, Jr. Nov 1977

Hypoxylon Mammatum Pathotoxin Responsible For Canker Formation In Quaking Aspen, Arthur L. Schipper, Jr.

Aspen Bibliography

No abstract provided.


Tree To Chips To Red Meat To Steaks, It Serves As Emergency Livestock Feed, Les Kamstra Jul 1977

Tree To Chips To Red Meat To Steaks, It Serves As Emergency Livestock Feed, Les Kamstra

Aspen Bibliography

We must be resourceful. Our "natural" resources are becoming scarcer every day, while waste products mushroom in dumps, along roadsides, in the water and air.


Importance Of Legumes, Especially The Trifolium Species, In Range Improvement, Abdelhai A. Ibnattya May 1977

Importance Of Legumes, Especially The Trifolium Species, In Range Improvement, Abdelhai A. Ibnattya

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This paper analyzes the most important characteristics of legumes, which have led to their utilization in range improvement all over the world. It emphasizes the Trifolium spp. (esteemed among the legume family), their contributions to soil a n d forage improvement, and the success obtained from their utilization, especially in semi-arid ranges. Many references originally from Australia, United States, Morocco, and Portugal were used as sources of data because of the ample utilization of these species in these countries. Careful analysis related to requirements, potentialities, and production of clovers were used and recommendations were made for different ecological areas where …


Competitive Interaction In Plant Populations Exposed To Enhanced Uv-B Radiation, Fred M. Fox May 1977

Competitive Interaction In Plant Populations Exposed To Enhanced Uv-B Radiation, Fred M. Fox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Competitive balance and changes in individual plant growth parameters of eight pairs of plant species exposed to enhanced UV-B irradiation were determined under field conditions simulating ozone reductions of about 0.08 atm·cm. The levels of irradiance represented ozone decreases of about 25-30 percent from approximate ambient ozone concentrations for high solar altitudes on clear days during the study. A method for calculating and statistically analyzing relative crowding coefficients was developed and used to evaluate the competitive status of the species pairs sown in a modified replacement series. The effect of UV-B irradiance was generally detrimental to plant growth, and was …


Relationships Of Vegetation To Environment In Canyonlands National Park, Walter Lee Loope May 1977

Relationships Of Vegetation To Environment In Canyonlands National Park, Walter Lee Loope

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The vegetation of Canyonlands National Park, Utah, has been described from 157 samples located throughout the Park. Species frequency, density and cover were recorded along with measurements of soil thickness, slope, aspect, elevation and geologic substrate at each site. Measurements of soil texture, pH, and electrical conductivity were taken for a representative subsample. A map of the vegetation of the Park was made by relating the sample points to their corresponding spectral signatures on vertical aerial photographs and locating boundaries between vegetation units by means of changes in photo signatures.

Vegetation in these arid to semi-arid environments appears to be …


Aspects Of The Life History Of Three Catostomids Native To The Upper Colorado River Basin, Charles W. Mcada May 1977

Aspects Of The Life History Of Three Catostomids Native To The Upper Colorado River Basin, Charles W. Mcada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The distribution, abundance and life history were studied for three catostomids -- the razorback sucker (Xyrauchen texanus), the flannel-mouth sucker (Catostomus latipinnis), and the bluehead sucker (Catostomus discobolus) -- all native to the upper Colorado River basin. The razorback sucker has declined in abundance due to man's impact upon the system and it has been recommended that this species be listed as ''threatened" on the U. S. Department of the Interior's list of Threatened or Endangered species [Personal corrmunication, G. C. Kobetich, U. S. Fish and Wildlife Service, Las Vegas, Nevada]. During this investigation, …


The Effect Of Four Mine Spoil Treatments On The Seedling Water Relations Of Two Plant Species, Lorraine K. Van Kekerix May 1977

The Effect Of Four Mine Spoil Treatments On The Seedling Water Relations Of Two Plant Species, Lorraine K. Van Kekerix

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Surface mines in mountainous areas cause environmental deterioration at lower elevations in the watershed. The most successful long term solution to the downstream problem is revegetation. However, mine spoils are low in essential plant nutrients, have low water holding capacity, and are often acidic. These factors limit plant colonization. Plants must also be adapted to the environmental conditions of high elevations.

At the McLaren Mine, }1ontana, at 2800 m, it was observed that seedlings on revegetation plots were desiccated, indicating possible water deficits. Field and growth chamber studies were carried out to determine the effects of some spoil ameliorating treatments …


Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza May 1977

Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to provide data on responses of Angora goats and blackbrush (Coleogyne ramosissima) to a biological manipulation program. Blackbrush utilization levels averaged 30, 16, and 6 percent (545, 367, and 147 kg per hectare) for the heavily, moderately, and lightly browsed pastures, respectively; removal rates of 77, 38, and 19 percent (1164, 582, and 291 kg per hectare) were projected.

Statistically significant differences in body weight loss (P=0.052) were noted for goats browsing in different replications. Goats lost an average of 14 and 19 percent of body weight in replications one and two, …


Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr. May 1977

Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rodent densities were estimated in the major vegetation types of the Snake River Birds of Prey Natural Area in 1975 and 1976 by a combination of live-trapping and kill-trapping. Only deer mice (Peromyscus maniculatus) were numerous enough to permit reliable density estimates. Relative densities of other rodent species were indicated by kill-trap capture rates. Densities of deer mice correlated well (r = 0.99) with kill-trap capture rates. The use of kill-trapping in place of live-trapping in 1976 permitted extensive sampling throughout the 1930 km2 study area. Differences were found among the major vegetation and land-use types in …


Sheep Behavior And Vulnerability To Coyote Predation, Ernest Albert Gluesing May 1977

Sheep Behavior And Vulnerability To Coyote Predation, Ernest Albert Gluesing

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the activity patterns and social relation ships between individuals in a large herd of domestic sheep (Ovis aries) in an effort to determine if behavioral characteristics predisposed certain individuals to coyote (Canis latrans) predation.

The research was conducted on the Cook Ranch near Florence, Montana, from March through September of 1975. Data were collected from a herd of 627 ewes and 1082 lambs, each individually identifiable. A random sample of 44 ewes and their 75 lambs were intensively studied over a 16-wk period to establish activity budgets and the relationships between sheep activity …


The Influence Of Predator Control On Two Adjacent Wintering Deer Herds, Dennis D. Austin, Philip J. Urness, Michael L. Wolfe Mar 1977

The Influence Of Predator Control On Two Adjacent Wintering Deer Herds, Dennis D. Austin, Philip J. Urness, Michael L. Wolfe

Aspen Bibliography

No abstract provided.


Jack Pine And Aspen Forest Floors In Northeastern Minnesota, Robert M. Loomis Jan 1977

Jack Pine And Aspen Forest Floors In Northeastern Minnesota, Robert M. Loomis

Aspen Bibliography

Characteristics of upland forest floors under mature jack pine and aspen in northeastern Minnesota were investigated.


Biomass Estimation For Some Shrubs From Northeastern Minnesota, David F. Grigal, Lewis F. Ohmann Jan 1977

Biomass Estimation For Some Shrubs From Northeastern Minnesota, David F. Grigal, Lewis F. Ohmann

Aspen Bibliography

Biomass prediction equations were developed for 23 northeastern Minnesota shrub species. The allometric function was used to predict leaf, current annual woody twig, stem, and total woody biomass (dry grams), using stem diameter class estimated to the nearest 0.25 cm class at 15 cm above ground level as the independent variable.


Natural Regeneration Of Northern Hardwoods In The Northern Great Lakes Region, Carl H. Tubbs Jan 1977

Natural Regeneration Of Northern Hardwoods In The Northern Great Lakes Region, Carl H. Tubbs

Aspen Bibliography

The forest types collectively known as "northern hardwoods" (Quigley and Babcock 1969) occupy nearly 100 million acres in eastern North America.


Aspen Mortality At The Maroon Lake Campground, Aspen Ranger District, White River National Forest, David W. Johnson, Thomas E. Hinds, G.L. Downing, F.A. Dorrell Jan 1977

Aspen Mortality At The Maroon Lake Campground, Aspen Ranger District, White River National Forest, David W. Johnson, Thomas E. Hinds, G.L. Downing, F.A. Dorrell

Aspen Bibliography

No abstract provided.


Some Individual Plant Biomass Values From Northeastern Minnesota, Lewis F. Ohmann, David F. Grigal Jan 1977

Some Individual Plant Biomass Values From Northeastern Minnesota, Lewis F. Ohmann, David F. Grigal

Aspen Bibliography

No abstract provided.


Vegetation And Environmental Features Of Forest And Range Ecosystems, George A. Garrison, Ardell J. Bjugstad, Don A. Duncan, Mont E. Lewis, Dixie R. Smith Jan 1977

Vegetation And Environmental Features Of Forest And Range Ecosystems, George A. Garrison, Ardell J. Bjugstad, Don A. Duncan, Mont E. Lewis, Dixie R. Smith

Aspen Bibliography

This is one of the reports developed as part of the Forest-Range Environmental Study (FRES) of the Forest Service, U.S. Department of Agriculture. This report presents descriptive sketches of 34 soil-vegetation units, called ecosystems. These cover all the land area of the 48 contiguous States.


Forest Insect And Disease Management : Aspen Mortality At The Maroon Lake Campground, David W. Johnson, Thomas E. Hinds Jan 1977

Forest Insect And Disease Management : Aspen Mortality At The Maroon Lake Campground, David W. Johnson, Thomas E. Hinds

Aspen Bibliography

At the request of the White River National Forest, Dave Johnson, Plant Pathologist, FI&DM and Tom Hinds, Plant Pathologist, RMFRES, made an evaluation of aspen mortality in the Maroon Lake Campground, Aspen Ranger District during June 13 to 15, 1977. Previously, Hinds (1976) reported accelerated aspen loss in 17 campgrounds, including Maroon Lake, located throughout Colorado and New Mexico (Fig. 1).


Biomasse D'Un Peuplement De Peuplier Faux-Tremble Age Six Ans, René Doucet Jan 1977

Biomasse D'Un Peuplement De Peuplier Faux-Tremble Age Six Ans, René Doucet

Aspen Bibliography

The establishment of an experiment designed to study the effect of thinning and fertilization in a 6 year-old trembling aspen stand, provided the opportunity to determine the mass of the standing crop present at the age.