<<

National Park Service National Capital Region Network U.S. Department of the Interior

Native Resource Brief

Importance Grapes are the most abundant native to the National Capital Region Network (NCRN). They support wildlife in many ways. Tangles of grapevines provide excellent cover

and nesting sites for songbirds as well as stringy for NPS/Nortrup NPS/Nortrup State of nesting material. Most importantly, grapevines produce All grapes in the NCRN except muscadine have stringy plentiful quantities of fresh consumed by and “shredded” bark (left) and grasping forked tendrils (cen- mammals from late summer through fall. Persistent dried ter). Some have glaucous (whitish or bluish) fruit (right) or of the winter and summer are a substantial . food source for winter resident songbirds such as the blue- fruit varies from as small as three millimeters in the winter birds, cedar waxwings, hermit thrushes, mockingbirds, and grape to as large as 2.5 centimeters in the fox and muscadine robins. In addition, serve as a primary food grapes. The presence or absence of a glaucous (bluish-whit- source for the larval stage of several native moth . ish) bloom on the fruit varies from species to species. undersides are substantially hairy in the fox, possum, and NPS/Nortrup Basics summer grapes and essentially hairless in the muscadine, There are about 60 species of riverbank, winter, and rock grapes. grapes () native to temperate A common grape look-alike is the non-native invasive por- regions of the Northern Hemi- celain (Ampelopsis brevipedunculata) . Porcelain sphere. Of twelve species native berry is an Asian member of the grape family with leaves to eastern , seven that closely resemble grape leaves. However, its bark never occur in the NCRN. Grapes are shreds or exfoliates and the pith inside the stem is white vines that climb using tendrils (instead of brown like grapes). The small (6-8mm) speck- that grasp onto branches and led porcelain berry turn pink, purple, and blue when other supporting objects. Many (http://www.nps.gov/plants/alien/fact/ambr1.htm). species can grow more than 100 feet in height and live to be more than 100 old. In fact the This grape vine, grow- NCRN Native Grape Species ing on C&O Canal’s oldest grapevine in the is Winter Grape () is by far the most common Cabin John Island could thought to be around 400 years easily be 100 years old. species of grape across the NCRN. It is found in moist old. upland and bottomland habitats. The black shiny fruits Grape products are familiar to people as table grapes, rai- are small (3-9mm) and persist on the vine into winter. The sins, jams, jellies, , and . Most commercial grape leaves are smooth and green on the underside. Due to its products are derived from the common grape () abundance, the winter grape is a significant source of food which is native to and southwest . However, for wildlife in our region. many domesticated North American species are popular in Summer Grape () is found in upland forests trade too. The human use of grapes for food and dates and is our second most abundant grape. It is readily identi- back thousands of years. fied by the glaucous color on the underside of the leaves. The moderately glaucous fruits are 5-12mm in diameter and Distinguishing Traits persist on the vine. This species is plentiful at Catoctin and Harpers Ferry. The wine grape is derived from this All grape species in the NCR except for the muscadine have species and is said to be the oldest domesticated American mature bark that shreds and exfoliates. The size of the grape grape.

http://science.nature.nps.gov/im/units/ncrn/index.cfm March 2012 National Park Service National Capital Region Network U.S. Department of the Interior

Possum Grape () is an uncommon species usu- Muscadine Grape () is native to sandy soils ally found on river bottomlands but occasionally in moist of the Coastal Plain. Although not known from any NCR to wet upland sites. The 4-8mm fruits are black with a slight park, this southern grape grows at Chapman State Park just Species glaucous bloom. Possum grape resembles summer grape downriver from Piscataway Park (NACE) and is known except the underside of the leaves are not glaucous and the from Arlington County, . The muscadine is our only fruits are only slightly glaucous. This southern species is grape without forked tendrils or stringy bark. The large (1.2- found mostly along the Anacostia and Potomac Rivers. 2.5cm) fruits drop when ripe. This species is grown com- mercially for wine and table grapes in the southern states. Fox Grape () is a wide ranging but uncommon Muscadine Published reports of this species from Antietam, Monocacy, (Vitis rotundifolia) species usually associated with wetlands. The fox grape is and Prince William are based on misidentifications. distinguished by its large fruits (1-2.5cm) and a dense fuzz (pubescence) that conceals the undersurface of the leaves. No other grape in our area has a dense felt covering the en- Threats tire leaf undersurface. The fruits drop soon after ripening. The is derived from this species. Grapevines are often cut by well-meaning but misinformed weed warriors and by trail maintenance crews. Sadly, this Fox Riverbank Grape () is usually found on alluvial (Vitis labrusca) practice has become fairly common in some NCRN parks. soils of large streams and rivers. The 8-13mm fruits have a Better training and supervision of crews is much needed heavy glaucous bloom. This species and summer grape are to reduce unnecessary impacts to these and other valuable our only blue colored grapes. However, riverbank grape native vines. lacks the glaucous color found on the underside of the leaves of the summer grape. This species is used as a - Riverbank stock for many wine grape . More on Vines (Vitis riparia) Rock Grape () is a rare species that grows in NCRN Inventory & Monitoring program monitors vines calcareous sands of scoured rocky riverbanks along the Po- like grape as part of a larger forest vegetation protocal. To tomac River. It is a somewhat shrubby, low climbing, sprawl- learn more about this monitoring, visit http://science.nature. ing species that bears few if any tendrils. Rock grapes have Summer nps.gov/im/units/ncrn/monitoring_veg.cfm to view the lat- (Vitis aestivalis) black, slightly glaucous fruits 6-10mm diameter that drop est reports and resource briefs. when ripe. Like the riverbank grape, rock grape serves as an important for many . Rock (Vitis rupestris) References

Brown, Russell G., M.L. Brown, Woody of Maryland, Port City Press, 1972. Winter Native vines including (Vitis vulpina) Moore, Michael O., Classification and Systematics of East- grape, Virginia creeper, ern North American Vitis L. () North of Mexico, Sida and others can some- 14(3):339-367, 1991. times become “cut vine Schmit, John Paul, P. Campbell, J. Parrish, 2012. National Capital collateral damage.” On Possum Region Network 2006-2009 Forest Vegetation Status Report, Nat- (Vitis cinerea) ural Resource Technical Report, National Park Service, Fort Col- the left, invasive orien- lins, CO. tal bittersweet (Celas- trus orbiculatus) and on Wagner, David L., of Eastern North America, Princ- eton University Press 2005. the right, native Virginia creeper (Parthenocisus quinquefolia). NPS/Nortrup Grapes of the National Capital Region

• Leaf or description Species Actual range of Found in which • Fruit size & coloration fruit size in mm NCRN parks • Habitat

• leaves small Found nearby but Muscadine • fruit 12-25mm not in any NCR (Vitis rotundifolia) • sandy soils, coastal parks plain

• leaf undersides fuzzy ANTI, CATO, CHOH, Fox • fruit 10-25mm GWMP, HAFE, NACE, (Vitis labrusca) • wetlands PRWI, ROCR, WOTR

ANTI, CHOH, GWMP • leaves not glaucous HAFE, NACE, ROCR Riverbank • fruit glaucous,* 8-13mm (Vitis riparia) • riverbanks

• leaf underside & fruits highly glaucous ANTI, CATO, CHOH, GWMP Summer • fruit glaucous, 5-12mm HAFE, MANA, MONO, NACE, (Vitis aestivalis) • upland forests PRWI, ROCR, WOTR

• shrubby, low growth Rock • fruit glaucous, 6-10mm CHOH, GWMP (contested) (Vitis rupestris) • rocky riverbanks

• leaf undersides smooth ANTI, CATO, CHOH, GWMP, & green Winter HAFE, MANA, MONO, NACE, • fruit 3-9mm (Vitis vulpina) PRWI, ROCR, WOTR • moist areas

• leaf undersides hairy CHOH, GWMP, NACE, PRWI Possum • fruit slightly glaucous, (Vitis cinerea) 4-8mm • river bottomlands

*glaucous = a bluish or whitish bloom

All grapes except muscadine ANTI = Antietam National Battlefield; CATO = Catoctin Mountain Park; CHOH = Chesapeake have stringy “shredded” bark, & Ohio Canal National Historical Park; GWMP = George Washington Memorial Parkway; HAFE and grasping forked tendrils. = Harpers Ferry National Historical Park; MANA = Manassas National Battlefield Park; MONO = Monocacy National Battlefield; NACE = National Capital Parks - East; PRWI = Prince William The pith inside grape stems is Forest Park; ROCR = Rock Creek Park; WOTR = Wolf Trap National Park for the Performing Arts brown.

All leaf photos by JK Marlow except V. cinerea by Jeffrey Pippen and V. aestivalis by D. Profant. Bark and tendril photos by NPS/Nortrup.