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A well-established riparian buffer is an efficient way to help keep Pennsylvania's waters clean.

Some 20,000 miles of Pennsylvania’s streams are impaired, according to figures from the state Department of Environmental Protection and the U.S. Environmental Protection Agency.

Much of that impairment is due to runoff from farmland, which famously sends sediment and nitrogen and phosphorus fertilizers downstream to the Chesapeake Bay.

Not so famously, those impaired waters affect the counties, townships and boroughs through which they flow. Even low levels of pollution can limit a stream’s potential for recreation, wildlife habitat, municipal water supplies and other uses.

Improved land management and wise fertilizer and herbicide applications by farmers, homeowners, municipalities and other landowners will go a long way toward improving the quality of local streams and the bay.

One of the most important tools for water quality management is the riparian buffer, according to the Penn State Extension educators who spoke in the March 19 webinar “Making Buffers Work for You.”

Jennifer Fetter, who leads the Extension water resources program, began the webinar with a map showing Pennsylvania’s forest land, which covers nearly 60% of the state.

Then she showed a map of the state’s impaired streams, which were noticeably absent from the forested area and very much in evidence in agricultural and urban areas.

Reforesting ag and urban streams has been happening slowly for decades, Fetter said, “but it really kicked into gear the last few years when a number of state agencies came together to set some very ambitious goals to get a lot more streams buffered before 2025.”

In 2016, the state set a goal of planting 95,000 acres of riparian forest buffers by 2025, a push that is now being managed by the Pennsylvania Bureau of Forestry.

Another ambitious program is the Keystone 10 Million Trees Initiative. The push, organized by the Chesapeake Bay Foundation, also has a deadline of 2025.

That’s the deadline for the federal-state bay cleanup program. Pennsylvania is behind on its ambitious commitments.

As part of that program, the state submitted to the EPA a watershed implementation plan that describes how Pennsylvania is going to meet its goals.

As part of the plan, Pennsylvania pledged to add 35-foot-wide forested buffers to 25% of streamside farmland by 2025.

The WIP calls for adding 83,000 acres of forested riparian buffers on agriculture lands, 2,650 acres of forested riparian buffers in developed or urbanized areas, and additional incentives to facilitate new acres of buffers associated with the state’s stormwater management program for urban areas.

Getting the Facts on Riparian Buffers

Tyler Groh, an Extension watershed management specialist, followed Fetter’s presentation with some riparian buffer basics, explaining what a buffer is, what it does and how it does it.

A minimal approach to promoting stream quality is a fence to keep livestock out of a stream. An exclusion fence doesn’t actually qualify as a buffer, but a grass strip between a fence and a stream will absorb some of the manure runoff from cattle.

A fence and a wide grass or meadow buffer are a good start at improving stream quality. But the ideal for Pennsylvania streams is a forested buffer, according to Groh.

Buffers improve infiltration of runoff before it enters a stream, provide habitat for wildlife and pollinators, stabilize stream banks with roots, offer shade and leaf litter for aquatic life, and keep fertilizer and manure out of the stream.

The cost of a buffer is low compared to the benefits it provides, and assistance and funding are available to start and manage them, Groh said.

Management is the key. Weeds have to be killed. The trees have to be cared for. And while some things, like berries, can be harvested from a well planned and managed buffer, row crops are pretty much out of the question.

One advantage accrues for any farmer who spreads manure on cropland.

DEP manure management regulations forbid any spreading within 100 feet of a stream if there are no conservation practices in place. The setback goes to 50 feet if a soil test shows less than 200 ppm of phosphorus, if the field is no-tilled and if it is covered by cover crops or crop residue.

The setback shrinks to 35 feet if there is a permanent vegetated buffer between the field and the stream bank.

Multiple Buffer Benefits 

Danielle Rhea, an Extension water resources educator in Jefferson County, closed the session with a discussion about the ultimate buffer which, as defined by the state, “is a riparian forest buffer that provides opportunities for harvesting products such as nuts, berries, woody florals, forbs and potentially woody biomass.”

The sky’s the limit, usually, in defining a harvestable product.

“The main idea behind the multifunction concept is that we can have both conservation and production benefits from these streamside areas,” Rhea said.

The multifunctional buffer typically has three zones.

In a model buffer, a 15-foot zone extends back from the water’s edge. It is unmanaged forest with native species of trees, bushes and other vegetation that tolerate a wet environment. They keep the stream bank intact.

Eroding stream banks contribute to sedimentation, but they also mean a loss of farmable land. In this first zone, herbicide use is allowed for weed control, but it should be minimized.

The second zone begins 15 feet in from water’s edge and extends another 15 to 20 feet beyond the stream.

It also consists of trees and shrubs, but with harvestable crops like nuts and berries. Herbicides can be used twice a year on vegetation in the second zone. Orchard species can be grown in the second zone.

Other species include paw paw, persimmon and black walnut trees. Nontree species include blueberries, raspberries and American hazelnuts.

Rhea said zone two is important to water quality because it is where nutrients are absorbed, pesticides are degraded and flood waters are slowed.

The use depends on the landowner, who may want to use mechanical harvesting equipment for fruits and nuts.

Zone three extends out from zone two for another 50 to 100 feet or more. Rhea said this zone is important to water quality because it is the first zone to intercept nutrients and stormwater.

Woody florals like dogwood and pussy willow are often found in this zone, both for their conservation value and for the marketability of their blossoms.

Warm- and cool-season grasses are often a part of the third zone, Rhea said, and they can be mechanically harvested and planted if they are perennial species.

More information about riparian buffer establishment and maintenance is available online at bit.ly/2QOlF2l.Penn State graphic

A well-established riparian buffer is an efficient way to help keep Pennsylvania’s waters clean.

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