NAAC_2-5B Windbreaks

Field boundary habitats are typically non-cropped areas adjacent to annual crops, usually consisting of trees and grass such as shelterbelts, road allowances, ditches, or wetlands. Producers often regard these areas as non-productive areas and potential negative influence on crop production. Often these areas are cleared to increase farmable areas. Specific information concerning the potential impact that field boundary habitats have on adjacent crops and how beneficial influences may extend into the field from the boundary is lacking for the Canadian agroecosystems. We hypothesized that field boundaries provide a mixture of habitats that contribute to the agroecosystem’s diversity and dynamics, with net positive impacts on carbon sequestration and (adjacent) crop production. To test this hypothesis, we: 1. spatially analyzed the extent and distribution of field boundary habitat influences on in-field variability using precision agriculture approaches, such as micro-scale in-field measurements of soil moisture, above- and below-ground biodiversity, insect pests, and weeds; and 2. quantified the benefits of conserving these non-crop areas on carbon sequestration, crop yield, and quality. We collected data from 42 sites representing one of two field boundary habitat types in the black soil zones of Saskatchewan, Canada: planted shelterbelt, natural hedgerow, and open fields with no field boundary habitat. Preliminary results indicated an increase in biodiversity and crop productivity in field boundary sites than open field sites. Alongside, quantification of stored carbon in selected shelterbelts demonstrated the value of these field boundaries in long-term sequestration of atmospheric carbon in tree/shrub biomass. The data is currently being analyzed. The intent is to provide science-based evidence for producers and other stakeholders on the functioning and value of field boundary habitats and the extent of their influence on adjacent field crops.

Fardausi Akhter, Agriculture and Agri-Food Canada

Additional authors:
Cory Sheffield, Royal Saskatchewan Museum
Julia Leeson, Agriculture and Agri-Food Canada
Jennifer Town, Agriculture and Agri-Food Canada
Laura Poppy, Agriculture and Agri-Food Canada
Luke Bainard, Agriculture and Agri-Food Canada
Raju Soolanayakanahally, Agriculture and Agri-Food Canada
Tricia Ward, Agriculture and Agri-Food Canada
William May, Agriculture and Agri-Food Canada

After the Dust Bowl in the 1930s, windbreaks become a more prominent way to reduce wind erosion. Windbreaks are single or multiple lines of trees and shrubs planted along the edge of agricultural lands. There are many other benefits from windbreaks, such as modifying airflow, wind speed reduction, and microclimate changes. Very few recent studies have evaluated the effect of windbreaks on crop yields. The main objective of this study was to evaluate the effect windbreaks have on modern crop yields. The specific objectives to identify the crops that exhibit improved yield due to windbreaks and are the yield increases enough to compensate for the windbreak footprint. Yield data were obtained from protected and unprotected fields across several counties in Kansas and Nebraska over several crop years. Windbreak influence on crop yield was developed using farmers’ pre-existing georeferenced data, generated by automated combine yield monitors, with ArcGIS 10.7.1 software. Yield loss was estimated from the windbreak footprint to see if yield increases are enough to compensate for the area taken out of crop production. Results showed that wheat had the most positive response to the windbreak effect with a yield increase of 62.9% of the time, with a 13.3% average yield increase. Soybean had the highest average yield increase with 20.9%. Yield increase from north and south windbreaks compensated for the windbreak footprint more often than east and west windbreaks. Overall, windbreaks provided inconsistent, but mostly positive yield benefits across a variety of crops.

Charles J. Barden, Department of Horticulture and Natural Resources, Kansas State University
Amila D. E. Mudiyanselage, Department of Horticulture and Natural Resources, Kansas State University

As the U.S. looks for strategies to achieve carbon drawdown, renewed interest has been placed on windbreaks as an approach to store carbon and avoid emissions. However, many producers across the U.S., especially those in the Great Plains, have aging windbreaks that need renovation or complete replacement. This raises an important question on whether producers still believe that windbreak benefits outweigh the costs, especially as producers adopt new farming practices, use new crop cultivars, and implement new technologies. To address this question, we conducted a systematic review of 32 U.S. windbreak adoption studies spanning from 1949 – 2020. Our objectives were to: 1) understand the primary benefits and challenges being reported by US producers using windbreaks, 2) assess how satisfied producers are with their windbreaks, 3) summarize what windbreak maintenance and management activities producers are reporting, and 4) assess the primary drivers affecting willingness or intent to adopt windbreaks and how those may vary by windbreak type (field, farmstead and livestock). This presentation will summarize our findings and end with a discussion of future research needs necessary to advance windbreak adoption.

Matt Smith, USDA National Agroforestry Center
Gary Bentrup, USDA National Agroforestry Center

Additional Authors:
Lord Ameyaw, Nebraska Forest Service
Todd Kellerman, USDA National Agroforestry Center
Katherine MacFarland, USDA National Agroforestry Center
Richard Straight, USDA National Agroforestry Center

In North America, hedgerows were planted by early European settlers who wanted to recreate their homeland landscapes, and to manage and protect soils. While in Europe hedgerow networks remained a key landscape feature, by the twentieth century in North America they had all but disappeared, primarily due to the modernization and intensification of agriculture. The North American hedgerow today is variously described as a fencerow, shelterbelt or windbreak with a variety of structures and uses but usually little or no management is regularly undertaken. There has been a resurgence of interest in hedgerows in North America this century which has come from two schools, agroforestry and socio-ecology, both resting on evidence for the growth of ecosystem services delivered by hedgerows. Agro-foresters are interested in hedgerows as living fences, in flood plain management and hydrology, pollination, carbon sequestration, crop pest management through natural enemies. Socio-ecologists value the use of hedgerows and the management practice of hedgelaying in creating a sense of place and improving human wellbeing. Hedgerow management is one of a number of rural skills and crafts which lend themselves to the concept of ‘Livelihood’ as place-based work envisioned as a solution to living within ecological limits to growth. In this paper we review the North American literature on hedgerows from the 1700s to the present day to explore if recent research reflects this rejuvenation of interest. We also report on initiatives to build on and coordinate interest: (i) ‘Hedgelaying in the Ontario Landscape’ at the University of Waterloo which has initiated hedgerow planting and management workshops to better understand how we might responsibly nurture socio-ecological novelty within settled regions; and (ii) the recent inauguration of the North American Hedgerow Society following hedgelaying workshops in Ithaca where there is significant interest in hedgerows as an agroforestry tool at the Cornell University and amongst local small-scale farmers in New York State and nearby Vermont.

Jame T Jones, University of Waterloo
Steve Gabriel,Wellspring Forest Farm/Cornell Small Farms Program
Nigel P. Adams, Nigel Adams Countryside Management
Rob Gil, Gilstead Fibers. Ryan Johnson University of Waterloo
Professor Stephen Quilley, University of Waterloo