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Compass July 2006
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Compass is a quarterly publication of the USDA Forest Service's Southern Research Station (SRS). As part of the Nation's largest forestry research organization -- USDA Forest Service Research and Development -- SRS serves 13 Southern States and beyond. The Station's 130 scienists work in more than 20 units located across the region at Federal laboratories, universites, and experimental forests.



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Issue 6

Working Trees Reconnect Land with Clean Water

by Michele Schoeneberger

Reconnecting Diagram

Reconnecting Diagram

Applied research from the SRS National Agroforestry Center in Lincoln, NE, can provide landowners in the Lower Mississippi Alluvial Valley (LMAV) with options to address erosion and flooding along their own streambanks—and, by extension, slow down the spread of the dead zone in the Gulf of Mexico.

The fertile soils and ideal climate that led to the outstanding diversity of species in the LMAV also helped create its rich agricultural heritage. Unfortunately, the massive land conversion to agriculture over the last two centuries has reduced the area’s natural habitat to only 10 to 20 percent of its original area. As the landscape has fragmented, the links among ecological processes have been pulled apart.

These shifts in land use have deteriorated the capacity of the land to provide critical ecosystems services such as clean water and wildlife habitat, and led to serious local problems such as polluted drinking and recreational waters, destabilized streambanks, and loss of indigenous plant and animal species. Pollution and sediment from the LMAV also contribute to the hypoxia that has caused the dead zone in the Gulf of Mexico.

Meanwhile, the profitability of agriculture has steadily declined over the past decades, threatening the livelihoods of landowners. Taken together, these problems bring into serious question the future ecological and economic health of the LMAV. Trying to address both these aspects in the mostly privately owned lands of the area will be challenging.

To preserve important wildlife functions in the area, groups such as Ducks Unlimited and The Nature Conservancy have focused on identifying and protecting the few remaining critical lowland forest patches such as the Big Woods Conservation Area in northern Louisiana. Other groups, including the Forest Service, are focusing on how to actually reestablish forests, or afforest, on agricultural lands, but nearly 80 percent of the 25 million acres in the LMAV are still in agricultural production. The average farm size is 300 acres—and most farmers are reluctant to convert their lands back to forests. More options are needed to help landowners participate in restoring ecological functions.

This is where the Working Tree practices, developed by the National Agroforestry Center, come in. Specifically designed to blend agricultural and forestry production, these tree-based practices provide a means to help reconnect and restore ecosystem functions across the highly fragmented LMAV landscapes while keeping the land in agricultural production.

A Win-Win Situation

Although there are many Working Tree practices that can address the area’s primary issues of water quality and wildlife, riparian forest buffers hold the most promise. By filtering, trapping, and bioprocessing sediment, fertilizer, and pesticide runoff from adjacent lands, riparian forest buffers protect and enhance water quality, while providing highly critical roosting, nesting, foraging, and travel habitat for wildlife. These same riparian forest buffers also provide greenhouse gas mitigation by sequestering significant amounts of carbon dioxide.

Planted in long thin strips, riparian forest buffers use a relatively small proportion of the land, allowing the farmer to still derive an annual income from traditional agricultural production. Depending on the objectives of the landowner, these plantings can be designed to also provide an additional source of annual income from either specialty forest products such as flowers or mushrooms, from hunting fees, and, in the longer term, from timber products. Best suited for marginal agricultural lands, Working Tree practices could create a real win-win situation, helping to restore the LMAV while providing real economic benefits to landowners.

There are multiple Federal, State, or other cost-share programs to help landowners establish these plantings. Getting the biggest bang for buffer-buck from these programs, however, requires locating these practices on the landscape where they can do the most good. The National Agroforestry Center develops the information and tools needed by natural resource professionals to help landowners plan and design Working Tree plantings for maximum benefit.

Efforts are focused on answering three basic questions: How do these buffers work? How do you build them? Where do you place them on the landscape? Tools are being developed to analyze spatial patterns of runoff and to design variable-width riparian forest buffers that better match location-specific needs. Other tools include GIS-guided assessments that help identify high priority patch and riparian connectivity areas, where certain agroforestry products can be grown, and where to locate buffers to best address waterquality issues. While these tools can be used separately, they work best when combined to provide multiple benefits from one planting.

Successfully restoring the LMAV depends on coming up with solutions that encompass the diverse concerns of its landowners, and requires collaboration among the many entities involved and across all its lands. Working Trees practices can connect across land ownerships while addressing multiple ecosystem services. For more about the full range of Working Trees practices, see Working Trees for Water Quality at http://www.unl.edu/nac/workingtrees/wtwq.pdf.

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Michele Schoeneberger is Project Leader of the SRS National Agroforestry Center located in Lincoln, NE.