The Silver Maple Forest (Belmont Uplands) & The Impact of Development Charles J. Katuska, MFS,PWS Consulting Ecologist “The aesthetic, wildlife, watershed protection, and wood production values of these (suburban) woods will increase in every future decade” - Lloyd Irland Presented to: The Belmont Planning Board On behalf of: Friends of Alewife Reservation and Belmont Citizens Forum Prepared by: Charles J. Katuska, P.W.S. 4 Upland Road Southborough, MA 01772 (508) 229-2608 11/28/2018

What Is It ? The Belmont Silver Maple forest is a mixed association of various wetland and upland plant communities on about 15 acres. Silver maple (Acer saccharinum) dominates the central core of the site. Unusual, relict forest community in this context The dominant stand of silver maple is located on the elevated central section of the site and is essentially a pure stand - very unusual for silver maple itself, which usually occurs in mixed hardwood stands along active floodplains. The silver maple forest is surrounded by various plant associations, all of which are more diverse collections of tolerant species and numerous invasive species, some of which are locally or extensively dominant 11/28/2018

The Belmont Silver Maple Forest ARLINGTON Route 2 Little Pond Acer saccharinum Even this aerial “close-up” provides a feel for the context of the site - a densely developed urban/suburban environment. Note the interspersion of diverse and valuable habitat/land cover types associated with the Belmont Upland site - forest, grassland, various vegetated wetlands, lacustrine and riverine environments. Recall proximity of Belmont Uplands site to extensive corridor or permanently protected open space - Alewife Reservation BELMONT CAMBRIDGE Little River 11/28/2018

Silver Maple (Acer saccharinum) A native floodplain tree species with specific autecological values - Provides an important wildlife food resource (newly broken buds) at a critical time of the late winter High value food source for beaver, second only to alders High value for cavity-nesting wildlife Shallow fibrous root system well adapted to reducing erosion and stabilizing soils Croxton, W. C. 1939. A study of the tolerance of trees to breakage by ice accumulation. Ecology 20:71-73. Eyre, F. H., ed. 1980. Forest cover types of the United States and Canada. Society of American Foresters, Washington, DC. 148 p. Hosner, J. F. 1960. Relative tolerance to complete inundation of fourteen bottom land tree species. Forest Science 6:246-251. Little, Elbert L., Jr. 1979. Checklist of United States trees (native and naturalized). U.S. Department of Agriculture, Agriculture Handbook 541. Washington, DC. 375 p. Nixon, C. M., and J. Ely. 1969. Food eaten by a beaver colony in southeast Ohio. Ohio Journal of Science 69:313-319. Prince, H. W. 1968. Nest sites used by wood ducks and common goldeneyes in New Brunswick. Journal of Wildlife Management 32:489-500. Reichard, T. A. 1976. Spring food habits and feeding behavior of fox squirrels and red squirrels. American Midland Naturalist 96:443A50. Sargent, C. 8.1905. Manual of the trees of North America. vol.2. Dover, New York. 910 p. Weitzman, Sidney, and R. J. Hutnik. 1965. Silver maple (Acer saccharinum L.). In Silvics of forest trees in the United States. p.63-65. H. A. Fowells, comp. U.S. Department of Agriculture, Agriculture Handbook 271. Washington, DC. 11/28/2018

This well-grown, diverse, and regionally uncommon forest stand exists in a unique context Forest stand averages 40’-50’ in height, 8”-12” DBH, and is fully stocked at 80-100 s.f./acre (basal area) Silver Maple forest stand is about 10-12 acres in extent, within a larger complex of associated habitats - red maple/ash forest edges, old field habitats, scrub-shrub areas, riverine forests The landscape has been significantly altered hydrologically, extensively filled, and invaded by less tolerant (“invasive”) plant species - European buckthorn, Oriental bittersweet, Norway maple, multiflora rose and others. Urban, suburban setting is very uncommon, essentially unique in this watershed 11/28/2018

Locally Unique Forest Context (USGS GAP Analysis for Biodiversity) Menotomy Rocks Park ARLINGTON Spy Pond BELMONT UPLANDS LITTLE POND GAP Forest datalayer is a derivative of the Southern New England Vegetation datalayer, a GAP project component. An image was created from the original data set by selecting the following landcover classes - Forested Wetland, Suburban Forest, Conifer, Mixed, Oak/Maple/Birch, Birch Dominant, Oak Dominant, Red Maple Dominant, Northern Hardwoods Classification System for SNE Gap Vegetation Map. 1997. http://bandersnatch.fnr.umass.edu/gap/vegclass.html Finn, John T. and Curtice Griffin. 1997. Southern New England Gap Analysis. (Poster from 1998 GAP annual meeting.) http://bandersnatch.fnr.umass.edu/gap/GapPoster97.html Habitat Classification. http://bandersnatch.fnr.umass.edu/pub/GIS592/class.txt. July 8, 1997. Slaymaker, Dana, K. Jones, C. Griffin, and J. Finn. Mapping Deciduous Forests in Southern New England using Aerial Videography and Hyperclustered Multi-Temporal Landsat TM Imagery. http://bandersnatch.fnr.umass.edu/pub/video/vidveg3.html April 23, 1997. Cambridgepark City Infirmary BELMONT CAMBRIDGE Fresh Pond 11/28/2018

The Belmont Silver Maple Forest Forested land always provides value to the urban environment Maintains and improves air quality Maintains and improves water quality Reduces volumes of stormwater runoff Provides important wildlife habitat Recreation Aesthetics Educational Value Air Quality Functions - Removes, transforms, or serves as “sink” for urban pollutants; CO2,, NOX, Particulates (dust) Moderates temperatures - limits “heat island” effect, provides and preserves moist microclimates Water Quality Functions - “Sink” for atmospheric nutrient deposition, SO2, NOX, micronutrients (some heavy metals) Soil-based pollutant adsorbtion/absorbtion Water Quantity Functions - Reduced rates & volumes of surface runoff Increased infiltration & maintenance of groundwater elevations Wildlife Habitat Functions - Site-specific habitat values (Area, soils, vegetation, diversity of habitat types) Refugia for urban/suburban wildlife Function within a larger mosaic of habitat patches 11/28/2018

The Belmont Silver Maple Forest Provides additional site-specific functions and values here - Serves as an important “core habitat” adjacent to Little Pond and the Alewife Reservation Size and Shape Land Cover Type Relative Seclusion in Context Provides a significant reserve within a network of other habitat patches for the continued preservation of area-sensitive species These are positive site-specific values, not just reviews of benefits due to the absence of development Site-specific habitat values Habitat Block size and shape is important, not the same as a collection of smaller parcels of same total acreage. Provides opportunity for forest interior species (thrushes, warblers, flying squirrels, not just common generalists (blue jay, starling, house sparrow, gray squirrel) Urban woodlands have 50% more bird species than suburban residential and 100% more species than urban residential (breeding season date - disparity even greater during winter. Tilgman, 1987) Refugia for urban/suburban wildlife in the local context. Species nesting or denning here have access to the entire Alewife Reservation corridor, but this site provides a relatively isolated “refuge” within the larger, more heavily fragmented environment. The site functions within a larger mosaic of habitat patches to support area-sensitive species (red-tailed hawk, peregrine falcon, great horned owl, beaver, coyote) which need larger overall ranges than commonly preserved in urban/suburban environments Silver maple itself has specific habitat value (critical food source, large cavities) not represented in other common urban woodland tree species 11/28/2018

Now, the Belmont Silver maple Forest is the site of a substantial development proposal - Project shown is as filed during the MEPA process and does not represent any residential on mixed use project which may currently under consideration Project to be located on the site’s highest land, which is the entirety of the silver maple stand. The majority of the important forest stand, if not all of it, will be lost to development Land to be “preserved” is a mix of community types, all of which are significantly altered by invasive species The argument that the remaining undeveloped land will be “improved”, either as wildlife habitat or in terms of recreation potential, is unsupportable 11/28/2018

How would the Development (commercial or residential) of the Silver Maple Stand affect Forest values ? Add pollutants and additional stormwater volume to an already stressed receiving water system Directly eliminate core wildlife habitat and reduce the quality of remaining habitats Reduce air quality in the immediate area and contribute to local/regional air quality problems Eliminate the opportunity for recreation in the development area itself and reduce the quality of the recreation experience in undeveloped portions of he site Eliminate the locally unique and regionally significant floodplain forest aesthetic experience Stormwater “Management” - The proposed development will add pollutants associated with urban stormwater (hydrocarbons, heavy metals, nutrients) to the already-stressed Little River/Alewife Brook system (Estimate annual loadings of 3.3 lbs Zn, 3.38 lbs. Pb, 0.88 lbs/Cu to the drainage system) The proposed development will add additional water volume to downstream receptors already burdened with flooding problems (Estimate annual increases 8,550 m3/yr - 2.26M g/yr) The proposed development will decrease the site’s ability to recharge groundwater, thereby threatening the hydrologic regime of the adjacent wetland areas Wildlife Habitat - Core function of the entire site will be lost (loss of forest interior species, area-sensitive species, cavity nesting species) Habitat value of the remaining landscape will be significantly degraded by edge effects (windthrow, increases in invasive species), light & noise pollution Function of this important reserve in the context of the larger mosaic of urban patches will be significantly reduced if not entirely lost 11/28/2018

Final Considerations The environmental values of the Belmont Silver Maple Stand are not solely related to wildlife habitat or the protection of its surrounding wetlands. The development of the Belmont Silver Maple Stand will substantially eliminate its forest values and will degrade the forest & forested wetland values of the remaining land and the adjacent public open space. Potentially significant forest values do not flow to the community under current private ownership. The Belmont Uplands site is, in essence, a significant and uniquely valuable open space. Consideration of the future of this parcel should include both economic considerations and environmental considerations, including not only the avoidance of negative environmental impacts but also the opportunity to garner long-term public benefit at local and regional scales. 11/28/2018