Stream ReLeaf began in 1996, carrying out the State’s commitment to the Chesapeake Bay Riparian Forest Buffer (RFB) Initiative . Mature buffers had been found to reduce nitrogen by 60 to 90+ percent, a major benefit for the efforts to reduce nutrients to the Chesapeake Bay by 40% . The RFB Initiative was developed to increase the rate at which forest buffers were established and conserved throughout the Bay Watershed, and adopted by Maryland, Virginia, and Pennsylvania in 1996.

The initial goal, 2010 miles by the year 2010, was ambitious, representing a tripling of the previous rate of buffer planting prior to 1996. Maryland committed to 600 of the 2010-mile goal. In late 1997, the first Conservation Reserve Enhancement Program (CREP) was announced in Maryland, an approach newly authorized by the 1996 USDA Farm Bill. The generous incentives stimulated a 10-fold increase in the rate of landowners signing up for buffer plantings (Fig. 1). An increase in incentive rates in 1998 raised sign-up rates even more. Consequently, Maryland met its 600-mile commitment in 2001 and doubled the commitment to 1200 miles. As Virginia and Pennsylvania began CREP as well in 1999 and 2000, the entire 2010-mile goal for the Chesapeake Bay watershed was met in 2002, eight years early. The 2000 Chesapeake Bay agreement anticipated this early achievement, and called for an expanded goal, which was set in 2003.

Directive 03-1 set a new goal of establishing 10,000 miles of buffers in the Chesapeake Bay Watershed by 2010, of which Maryland is accountable for 2032 miles. Additional goals include establishing buffers along 70% of streams and rivers, working with five other jurisdictions to increase urban tree canopy cover, and to restore, promote and protect riparian forest buffers on public and private land.

Currently the Tributary Strategies Workgroup of the Nutrient Subcommittee of the Chesapeake Bay Program is looking at proposals from a team lead by the University of Maryland. The UMD team has recommended lowering riparian forest buffer efficiencies from their present levels, which will require revisions to current goals in order to meet nutrient caps. However the Forestry Work Group of the Chesapeake Bay Program is recommending efficiencies similar to those already in use. These, and other recommendations, will be taken into consideration by the Chesapeake Bay Program, which will set new percentages in the near future.

The Stream Releaf Implementation Plan for 2005-2010 is currently available. The plan outlines the new goal for the Stream Releaf program, which is an additional 1,200 miles between 2003 and 2010, and the strategy for reaching the goal. NOTE: the plan is an Adobe Acrobat file (330 KB). For the free Acrobat viewer go to Adobe.com.

To include a forest buffer in the statewide accounting, please send the buffer reporting form to:

Chesapeake Watershed Forestry +Coordinator:
580 Taylor Avenue, E-1
Annapolis, MD 21401
(410) 260-8531 or -8509

Buffer plantings can also be reported through an internet based reporting site at the Chesapeake Bay Program .

Riparian Forest Buffer Survival and Effectiveness

The statewide stocking survey of 130 buffer sites found that 82% met acceptable stocking levels (greater than 200 trees/acre) . Just over half of the sites exceeded preferred stocking levels of 400 trees/acre. Average stocking was 488 trees/acre, slightly lower than the average planting density of 511 trees/acre. Survival of planting seedlings was estimated to average only 60%, with naturally regenerated volunteer seedlings making up a third (36%) of the surviving seedlings. The new buffers are fairly diverse in composition, with an average of over 8 species per site. Weed competition was identified as the most common stressor for the young seedlings, with drought, deer, machinery such as mowers, and insects also being noted with lesser frequency.

A follow-up survey in 2002 found survival rates improved to 78%, attributed to greater attention to and support for maintenance by the CREP program. With increased mowing and spraying, the contribution of natural regeneration was reduced but still significant at 25% of total stocking.

Characteristics measured to establish baseline conditions for riparian forest buffer functions included vegetation composition, stream temperature, buffer cross-section and plan section, stream nitrogen and phosphorus, and benthic macroinvertebrate index of biotic integrity. Measurements were taken at fourteen locations in the Monocacy and Antietam watersheds in Frederick and Washington County in 2000 and 2001. Initial measurements found an average of 59 plant species per site (herbaceous and woody) and average daily maximum stream temperatures that rose from 21.4oC to 22.0oC from upstream to downstream, compared to standards of 20oC for natural trout reproduction and 23.7oC for a recreational trout fishery. Grab samples of streamflow (baseflow) nitrate and phosphate averaged 3.4 mg/l and 0.13 mg/l respectively. Water samples were within drinking water standards for nitrate (none are set for P), but higher than would be expected from a forested watershed. The Index of Biotic Integrity for benthic macroinvertebrates averaged 2.65, a rating of poor. These indices show that there is room for substantial improvement in water quality and habitat conditions in the future.

Invasive plants can be a major problem for early growth and survival of trees. Japanese hops is a recent invader that is most prolific in floodplains, and has been spreading rapidly along the streams of the Maryland Piedmont. To improve knowledge on how to control this problem in riparian plantings, Philip Pannill led a study and developed a Cooperative Weed Management Area for the Monocacy and Antietam watersheds. The project was funded through the National Fish and Wildlife Foundation with USDA Forest Service support. The results are presented in a report on the study results and recommendations, and a Powerpoint presentation that details plant biology and identification as well as results of different mechanical and chemical treatment methods.