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Quantifying Residual Forest Structures Following Retention Harvesting In Northeast Minnesota Using Landsat Sensor Data, Louis Hilgemann Jan 2015

Quantifying Residual Forest Structures Following Retention Harvesting In Northeast Minnesota Using Landsat Sensor Data, Louis Hilgemann

Graduate Theses and Dissertations

Restoration based forest management has increased significantly over the last decade across North America. Retention harvesting shows promise for restoring and maintaining forest structural and compositional diversity and also increasing resilience and adaptive capacity. This includes deliberate retention of large living trees, snags and downed woody debris (DWD). However, lack of consistent monitoring limits our understanding of the effectiveness of these strategies and our ability to adapt management accordingly. We investigate the use of readily available Landsat sensor data to remotely estimate and map DWD and basal area (BA) following retention harvesting in northeastern Minnesota, USA. We used multi-temporal winter ...


Impacts Of National Forests In The West On County Population And Employment, Andrew Pugliese, Laura Mccann, Georgeanne M. Artz Jan 2015

Impacts Of National Forests In The West On County Population And Employment, Andrew Pugliese, Laura Mccann, Georgeanne M. Artz

Economics Publications

This study seeks to understand the manner and extent to which western national forests influence an area's overall population and employment growth by evaluating changes in management emphasis from single to multiple uses. The Carlino and Mills model was used to examine county level data from 12 western states over the period 1977–2010. Changes in timber sales and the amount of land owned by the Forest Service were not found to be significantly related to employment growth.


Use Of Remote Sensing To Quantify Forest Response Following A Wildfire In Northeast Minnesota, Rayma Anne Cooley Jan 2014

Use Of Remote Sensing To Quantify Forest Response Following A Wildfire In Northeast Minnesota, Rayma Anne Cooley

Graduate Theses and Dissertations

Wildfire is a natural disturbance common to many forested ecosystems of North America. In the fall of 2011, a lightning-ignited wildfire, the Pagami Creek Fire (PCF), burned over 38,000 hectares of forest in northeast Minnesota, most of which occurred in the protected Boundary Waters Canoe Area Wilderness (BWCAW).

Satellite remote sensing data has been used within the upper Midwest to detect and quantify forest vegetation extent, composition, and associated structure. However, very few studies have quantified the composition and structure of early seral forest regeneration.

We were interested in two objectives:

1) Use a combination of remote sensing imagery ...


Carbon Dynamics In The Tropics, Ann E. Russell, James W. Raich, Ricardo Bedoya Arrieta, Oscar Valverde-Barrantes, Eugenio González Apr 2010

Carbon Dynamics In The Tropics, Ann E. Russell, James W. Raich, Ricardo Bedoya Arrieta, Oscar Valverde-Barrantes, Eugenio González

Natural Resource Ecology and Management Publications

Native tree species differed in their effects on above- and belowground carbon stocks and fluxes in these 16-yr-old experimental plantations at La Selva Biological Station, Costa Rica. Results were explained primarily by differences in growth rates, C allocation, turnover rates, and tissue chemistry. In this experiment established in an abandoned pasture, all five tree species had attained biomass amounts similar to that of nearby mature forest, whereas the abandoned pasture control remained in arrested succession. Carbon sequestration averaged 5.2 Mg∙ha-1∙yr-1 across species, close to the annual per capita fossil-fuel use in the United States of 5.3 ...


Effects Of Grazing Management On Pasture Production And Phosphorus Content Of Forage (A Progress Report), Mathew M. Haan, James R. Russell, Wendy J. Powers, Steven K. Mickelson, Syed I. Ahmed, John L. Kovar, Richard C. Schultz Jan 2003

Effects Of Grazing Management On Pasture Production And Phosphorus Content Of Forage (A Progress Report), Mathew M. Haan, James R. Russell, Wendy J. Powers, Steven K. Mickelson, Syed I. Ahmed, John L. Kovar, Richard C. Schultz

Beef Research Report, 2003

In spring 2001, pastures were grazed at the ISU Rhodes Research and Demonstration Farm to determine the effects of grazing management on pasture productivity and phosphorus (P) content of forage. Treatments included an ungrazed control, summer hay harvest with winter stockpiled grazing, continuous stocking to a residual height of 2 inches, rotational stocking to a residual height of 2 inches, and rotational stocking to a residual height of 4 inches. Forage production was greatest in June and July, decreased in August, and had a slight rebound in September and October before going dormant in November. Phosphorus concentration of forage was ...


Tree Biomass Productivity Project, Carl Mize Jan 2003

Tree Biomass Productivity Project, Carl Mize

Iowa State Research Farm Progress Reports

Fast-growing tree species, such as cottonwood (Populus spp.) and willow (Salix spp.), grow naturally throughout the Midwest, primarily along streams, and are excellent candidates for a new crop to grow on floodable sites. Other species, such as certain hybrid cottonwoods, are well suited to highly erodible lands (HELs). All of these species might be productive on normal agricultural soils. These types of trees can be used to establish plantings that can be harvested in 8 to 10 years and will re-sprout after harvest to produce another crop.


Effects Of Grazing Management On Sediment And Phosphorus Losses In Run-Off (A Progress Report), Mathew M. Haan, James R. Russell, Wendy J. Powers, Steven K. Mickelson, Syed I. Ahmed, John L. Kovar, Richard C. Schultz Jan 2003

Effects Of Grazing Management On Sediment And Phosphorus Losses In Run-Off (A Progress Report), Mathew M. Haan, James R. Russell, Wendy J. Powers, Steven K. Mickelson, Syed I. Ahmed, John L. Kovar, Richard C. Schultz

Beef Research Report, 2003

In 2001 and 2002, pastures at the ISU Rhodes Research and Demonstration Farm were grazed to determine the effects of stocking treatment on nutrient and sediment loss from pastureland. Treatments included an ungrazed control (UG), summer hay harvest with winter stockpiled grazing (HS), continuous stocking to a residual height of 2 inches (2C), rotational stocking to a residual height of 2 inches (2R), and rotational stocking to a residual height of 4 inches (4R). At three times in 2001 (late spring, mid-summer, and fall) and four times in 2002 (early spring, late spring, mid-summer, and fall), rainfall simulations were conducted ...


Get Acquainted With The Iowa Crep, Thomas M. Isenhart, Michael J. Tidman Jun 2002

Get Acquainted With The Iowa Crep, Thomas M. Isenhart, Michael J. Tidman

Integrated Crop Management News

The Conservation Reserve Enhancement Program (CREP), an offshoot of the original Conservation Reserve Program (CRP), is a voluntary program for agricultural landowners. Unique state and federal partnerships allow producers to receive incentive payments for installing specific conservation practices. Through CREP, farmers with eligible land receive annual rental payments and cost-share assistance to establish long-term, resource-conserving cover.


Maintenance Of Riparian Buffers, Iowa State University Extension And Outreach Mar 2002

Maintenance Of Riparian Buffers, Iowa State University Extension And Outreach

Agriculture and Environment Extension Publications

Riparian buffers are effective at reducing non-point source pollution in streams. However, to maintain their effectiveness they must be managed and maintained. Regularly scheduled maintenance should begin immediately after the buffer has been planted. It is also important to carefully inspect your buffer annually or after major storm events for any damage or problems that may have occurred. Repairs should be completed as soon as possible to maintain proper buffer functions. There are four major maintenance procedures outlined in this brochure. These four procedures are energy intensive and should be done at specifi c times during the growing season.


Forage And Tree Experiment (Fate), Eric Holzmueller, Carl Mize Jan 2002

Forage And Tree Experiment (Fate), Eric Holzmueller, Carl Mize

Iowa State Research Farm Progress Reports

Trees are becoming an increasingly important component of the Iowa landscape. For tree plantings to be more common in Iowa, two major problems related to establishment must be overcome: (1) intense weed competition and (2) lack of market or nonmarket values for several years for newly planted trees. To develop information that addresses these problems, a research project was initiated during the spring of 1998 at the Rhodes Research Farm.


Soybean-Based Wood Adhesives For Structural Panels , In Yang Jan 2002

Soybean-Based Wood Adhesives For Structural Panels , In Yang

Retrospective Theses and Dissertations

Recent research attention has focused on soybean-based adhesives because of increased phenolic resin prices and adhesive demand. This study was conducted to investigate the adhesive properties of crosslinked soy flour and/or soy hydrolyzate with phenol-formaldehyde (PF) resins for use in structural panels. Neutral phenolic soy (NPS) and alkaline phenolic soy (APS) resins were prepared and used to bond southern pine plywood. Adhesive bond quality of the soybean-based phenolic resins was evaluated by glueline shear test following the procedure detailed in Product Standard PS 1-95 for construction and industrial plywood. Within the range of variable levels investigated, the following conditions ...


Improving Tree Establishment With Forage Crops, Carl W. Mize, E. Charles Brummer, Kathleen Delate, Patricia Negreros-Castillo, Joseph P. Colletti Jan 2002

Improving Tree Establishment With Forage Crops, Carl W. Mize, E. Charles Brummer, Kathleen Delate, Patricia Negreros-Castillo, Joseph P. Colletti

Leopold Center Completed Grant Reports

Weed competition and economics are two common barriers to Iowa farmers' investing in tree plantings. This project examined seven weed control strategies and investigated productivity of small grain/forage combinations raised with trees in an effort to suggest management options that would encourage tree planting in the state.


A Hydrologic Study Of The Bear Creek Watershed Using Gis And The Hec-Hydrologic Modeling System, Rodney Kenyal Jones Jan 2001

A Hydrologic Study Of The Bear Creek Watershed Using Gis And The Hec-Hydrologic Modeling System, Rodney Kenyal Jones

Retrospective Theses and Dissertations

HEC-GeoHMS was used as a precursor for preprocessing data before input into HEC-HMS. A GIS soil's layer containing Iowa Soil Properties and Interpretations Database (ISPAID) was analyzed for this project. The analysis included a query within GIS of the flood frequency code to identify soil polygons that were labeled PONDED. These soil polygons were then displayed as an image within the boundaries of the Bear Creek watershed. GIS was used to calculate the amount of water (volume) that each of these soil polygons can hold. Changes in discharge under different storm events were calculated and displayed based on discharges ...


Forage And Tree Experiment (Fate), Carl Mize, Joseph P. Colletti, Patricia Negreros-Castillo, E. Charles Brummer, Kathleen Delate Jan 2001

Forage And Tree Experiment (Fate), Carl Mize, Joseph P. Colletti, Patricia Negreros-Castillo, E. Charles Brummer, Kathleen Delate

Iowa State Research Farm Progress Reports

Trees are becoming an increasingly important component of the Iowa landscape. For tree plantings to be more common in Iowa two major problems related to establishment must be overcome: (1) intense weed competition and (2) a lack of market or non-market values for several years for newly planted trees. To develop information that addresses these problems, a research project was initiated during the spring of 1998 at the ISU Rhodes Research Farm. The objectives of the project are: (i) to evaluate the influence of seven weed control treatments [four small grain/forage crop combinations (oats and red fescue; oats, red ...


Collecting Landscape Trees And Shrubs In Ukraine For The Evaluation Of Aesthetic Quality And Adaptation In The North Central United States, Mark P. Widrlechner, Robert E. Schutzki, Vasily Y. Yukhnovsky, Victor V. Sviatetsky Jan 2001

Collecting Landscape Trees And Shrubs In Ukraine For The Evaluation Of Aesthetic Quality And Adaptation In The North Central United States, Mark P. Widrlechner, Robert E. Schutzki, Vasily Y. Yukhnovsky, Victor V. Sviatetsky

NCRPIS Publications and Papers

Past experiences with long-term evaluations of woody landscape plants from Slovenia, Croatia, and Bosnia- Herzegovina in the north central United States indicated that a relatively low proportion of these introductions were well adapted to climatic and soil conditions. Based on these results, criteria were developed to focus future exploration for landscape trees and shrubs from more analogous environments in eastern and central Europe. Application of these criteria identified the forest– steppe transition zone in the northern half of Ukraine as a region with great potential, because of similarities to the north central United States in climatic extremes, soil types and ...


Soil Aggregate Dynamics And Aggregate-Associated Carbon Under Different Vegetations Types In Riparian Soils , Carmen Omaira Marquez Jan 2001

Soil Aggregate Dynamics And Aggregate-Associated Carbon Under Different Vegetations Types In Riparian Soils , Carmen Omaira Marquez

Retrospective Theses and Dissertations

Forest and grass riparian buffer systems provide year-round soil cover, limiting erosion, and favoring soil development processes by potentially increasing soil C sequestration. Plant-soil interactions influence patterns of soil aggregation and organic matter storage. And have a major positive impact on the soil ecological functions that maintain and enhance both water and environmental quality. In this dissertation a new theoretical and experimental framework is presented that introduces the concept and determination of aggregate size-stability distribution. In addition, two new indexes, the soil stability index and the total soil stability index, both based on aggregate, are proposed for studying soil stability ...


Response Of Plant Growth And Development To Different Light Conditions In Three Model Plant Systems , Hanhong Bae Jan 2001

Response Of Plant Growth And Development To Different Light Conditions In Three Model Plant Systems , Hanhong Bae

Retrospective Theses and Dissertations

Shade avoidance response to the reduced ratio of red:far-red (R:FR) light was studied in a white aspen Populus alba clone 'Bolleana' using two filter systems: a clear plastic filter system that allows a R:FR ratio less than 1.0 to pass from adjacent border plant reflection; and a special commercial plastic that blocks FR light and creates a R:FR ratio above 3.0. The response to low R:FR The reduced R:FR signals enhanced the stem elongation in response to competition at the expense of relative stem diameter growth. Trees grown inside clear chambers were ...


Evaluation Of Three Cropping Systems Grown Under The Influence Of A Shelterbelt, Carl W. Mize, Arne Hallam, Richard M. Cruse Jan 2001

Evaluation Of Three Cropping Systems Grown Under The Influence Of A Shelterbelt, Carl W. Mize, Arne Hallam, Richard M. Cruse

Leopold Center Completed Grant Reports

Shelterbelts have the potential to influence growth and yield from various cropping systems. On-farm tests were conducted to determine how shelterbelts interacted with corn, corn/soybean, and strip intercropping.


Biomass, Carbon, Nitrogen And Soil Respiration Dynamics Within Riparian Buffers And Adjacent Crop Fields , Aydin Tufekcioglu Jan 2000

Biomass, Carbon, Nitrogen And Soil Respiration Dynamics Within Riparian Buffers And Adjacent Crop Fields , Aydin Tufekcioglu

Retrospective Theses and Dissertations

Natural and re-established riparian buffers reduce nonpoint-source pollutants derived from upland agricultural lands and enhance terrestrial and aquatic habitat. This study was conducted in multi-species riparian buffers, cool-season grass buffers and adjacent crop fields to determine biomass, carbon, nitrogen and soil respiration dynamics. The multispecies buffers were composed of poplar (Populus x euroamericana' Eugenei ) and switchgrass (Panicum virgatum L.). Crop fields were under annual corn-soybean rotation. Aboveground biomass was determined by clipping grasses in 25 x 25 cm quadrats. The dynamics of fine (0--2 mm) and small roots (2--5 mm) were assessed by sequentially collecting 5.4 cm diameter, 35 ...


Tree Spacings And Red:Far-Red Light Effects On Juvenile Populus Growth And Morphology , Sovith Sin Jan 2000

Tree Spacings And Red:Far-Red Light Effects On Juvenile Populus Growth And Morphology , Sovith Sin

Retrospective Theses and Dissertations

Cottonwood stem growth and biomass accumulation are altered by changes in the red to far-red light ratio (R:FR). Genetic variation in this response might be exploited to improve yield. The first objective of this study was to detect the R:FR signals that affect important morphological traits and biomass accumulation under field conditions. The second objective was to compare the effect of R:FR signals on growth traits under greenhouse conditions. The third objective was to compare genotypic variation in responses to R:FR ratio changes. We focused on morphological traits (such as height, diameter, stem taper, and branching ...


Evaluation Of Interactions Within A Shelterbelt Agroecosystem, Carl W. Mize, William D. Batchelor, Richard M. Cruse Jan 2000

Evaluation Of Interactions Within A Shelterbelt Agroecosystem, Carl W. Mize, William D. Batchelor, Richard M. Cruse

Leopold Center Completed Grant Reports

Yield data for corn (eight years) and soybeans (six years) were collected and analyzed to determine the impacts of a hybrid poplar shelterbelt on crop production on a central Iowa farm.


Riparian Buffer Systems -- The Basics, Thomas M. Isenhart, Michael J. Tidman Jun 1999

Riparian Buffer Systems -- The Basics, Thomas M. Isenhart, Michael J. Tidman

Integrated Crop Management News

If you have a stream running through your farm, you may be interested in learning about a conservation technique that has gained the respect of many Iowa landowners and conservation professionals. It is called a riparian buffer system and involves planting trees, shrubs, and native grasses along streams to prevent sediment and chemicals from entering creeks and rivers.


Spatio-Temporal Modeling In An Agricultural Watershed , Shabana Hameed Jan 1999

Spatio-Temporal Modeling In An Agricultural Watershed , Shabana Hameed

Retrospective Theses and Dissertations

Non-point source pollution in agricultural regions in the Midwest consists of two important components, namely, dislodgment of common pollutants, their movement across the landscape and subsequently transport through surface waters to their final destination. The objectives of this study were to: 1) model surface movement of agricultural pollutants for a succession of sub-watersheds in Bear Creek using AGNPS; 2) calibrate and validate the model for a small sub-watershed using available experimental plot data; 3) incorporate Monte Carlo simulation within the modeling process where field data was not available; 4) apply the calibrated and validated model to a small sub-watershed with ...


Effectiveness Of A Multi-Species Riparian Buffer System For Sediment And Nutrient Removal , Kye-Han Lee Jan 1999

Effectiveness Of A Multi-Species Riparian Buffer System For Sediment And Nutrient Removal , Kye-Han Lee

Retrospective Theses and Dissertations

Nonpoint source (NPS) pollution from agricultural areas is one of the most critical problems threatening the nation's water resources. Surface runoff is a major carrier of NPS pollutants. Riparian buffers have been proposed as a means of reducing transport of NPS pollutants from agricultural areas to streams. Using rainfall simulation techniques and natural runoff monitoring, plot studies were conducted to evaluate the ability of an established multi-species riparian buffer system to reduce sediment and nutrient in agricultural runoff. The buffer system evaluated contained three types of vegetation: cool-season grasses, warm-season grasses, and woody plants. Results indicated that the effectiveness ...


Social Forestry Program In The Majalengka Forest District, West Java, Indonesia: Agroforestry Systems And Extension Services , Mamun Jan 1998

Social Forestry Program In The Majalengka Forest District, West Java, Indonesia: Agroforestry Systems And Extension Services , Mamun

Retrospective Theses and Dissertations

Farmers need land to grow food and the government needs forests to grow timber and protect water resources. Social forestry is thought to meet these needs. A study was conducted in the Majalengka forest district, West Java, Indonesia to evaluate the efficiency and adoptability of a social forestry program (SFP) including its associated extension services. Data were collected in 1996-1997 from program personnel and a sample of 101 forestry farmers. Agroforestry systems economics, adoption models of new agroforestry techniques, and the extension program were evaluated. Farmers joined the SFP because they need additional family income and land. Mahogany, pine, Albizzia ...


The Poplar-Leaf Rust Pathosystem: Inheritance Of Resistance And Pathogenic Variability , Girma Melesse Tabor Jan 1998

The Poplar-Leaf Rust Pathosystem: Inheritance Of Resistance And Pathogenic Variability , Girma Melesse Tabor

Retrospective Theses and Dissertations

Among diseases that cause serious yield reduction on Populus deltoides is leaf rust caused by Melampsora medusae. The objectives of this project were to study the pathogenic variability of M. medusae, the genetic basis of inheritance of M. medusae resistance in a family of P. deltoides; and to identify molecular markers linked to a leaf-rust resistant locus. Three pathotypes of M. medusae were identified on the basis of their differential reaction to three Populus clones. Pathotypes D-93, F-93, and IL-48 were compatible with clone 1-488 (P. X euramericana). F-93 and IL48 were also compatible with clone 57-276 (P. deltoides X ...


Shelterbelt: Soybean Production Model (Sbelts) , Xiaoming Qi Jan 1998

Shelterbelt: Soybean Production Model (Sbelts) , Xiaoming Qi

Retrospective Theses and Dissertations

Wind may desiccate and cause direct mechanical injury to plants. Shelterbelts, which reduce wind speed, can be beneficial to crops grown near them. However, they are not often used in the United States because there is not adequate economic information that clearly shows their benefits. It is difficult to obtain the information because shelterbelts grow slowly, taking many years to show a yield improvement, and there are also an enormous number of combinations of crops, soil types and types of shelterbelts to consider. An alternative approach to evaluating the combinations is to develop a computer model that can simulate the ...


Incorporation Of A Subsurface Tile Drainage Component Into A Soybean Growth Model, Jinmei Shen, William D. Batchelor, Rameshwar S. Kanwar, James W. Jones, Joe T. Ritchie, Carl W. Mize Jan 1998

Incorporation Of A Subsurface Tile Drainage Component Into A Soybean Growth Model, Jinmei Shen, William D. Batchelor, Rameshwar S. Kanwar, James W. Jones, Joe T. Ritchie, Carl W. Mize

Agricultural and Biosystems Engineering Publications

A simple tile drainage model was incorporated into a recent version of the CROPGRO-soybean model. The model was calibrated and validated using four years of data from the Water Quality Research site, located at the Iowa State University Northeast-Research Center near Nashua, Iowa having two soil types (Readlyn and Kenyon). The data consisted of measurements of soil water contents at different depths and times, cumulative monthly tile flow, and final crop yield from 36 different 0.41 ha plots that were individually tile drained. The model was calibrated to give the best fit between the predicted and measured tile flow ...


Demonstration Of An Agroforestry System To Minimize Pollution Hazards From Land Application Of Treated Municipal Sludge, Joseph P. Colletti, Michael L. Thompson, Richard C. Schultz, Carl W. Mize, Irvin Anderson Jan 1998

Demonstration Of An Agroforestry System To Minimize Pollution Hazards From Land Application Of Treated Municipal Sludge, Joseph P. Colletti, Michael L. Thompson, Richard C. Schultz, Carl W. Mize, Irvin Anderson

Leopold Center Completed Grant Reports

Iowa has over 700 communities that generate municipal biosolids by various treatment means. These biosolids contain valuable nutrients. In this study, municipal biosolids are applied to trees, perennial grasses, and corn/soybean crops in an alley cropping (repeated tree strips combined with crops) system. The goal is to produce economical quantities of biomass and grains with reduced use of fossil fuel-based fertilizers and minimal environmental impacts.


Buffer Strip Design, Establishment, And Maintenance, Richard C. Schultz, Paul H. Wray, Joseph P. Colletti, Thomas M. Isenhart, Charles A. Rodriguez, Amy Kuehl Apr 1997

Buffer Strip Design, Establishment, And Maintenance, Richard C. Schultz, Paul H. Wray, Joseph P. Colletti, Thomas M. Isenhart, Charles A. Rodriguez, Amy Kuehl

Agriculture and Environment Extension Publications

This publication discusses how to design, plant, and maintain a multi-species buffer strip, which is an important part of river ecosystems.