Transcription

A Field Guide to Selected Trees and Shrubsof theUniversity of Massachusetts DartmouthCampusWritten and Illustrated by:Richard H. UvaClass of 1991Department of BiologyUniveristy of Massachusetts DartmouthNorth Dartmouth, MAEdited by:James R. SearsProfessor of BiologyUniversity of Massachusetts DartmouthConverted to Web Format by:Sustainability Studies Seminar ClassSpring 2012University of Massachusetts Dartmouth1

TableofContentsREDMAPLEȂACERRUBRUM.4YELLOWBIRCH- ‐BETULALUTEA.6GRAYBIRCH- ‐BETULAPOPULIFOLIA.8SWEETPEPPERBUSH- ‐CLETHRAALNIFOLIA.10SWEETFERN- ‐COMPTONIAPEREGRINE.11FLOWERINGDOGWOOD- ‐CORNUSFLORIDA.13AMERICANBEECH- ‐FAGUSGRANDIFOLIA.15WITCH- ‐HAZEL- ‐HAMAMELISVIRGINIANA.17INKBERRY- ‐ILEXGLABRA.18AMERICANHOLLY- ‐ILEXOPACA.19WINTERBERRY- ‐ILEXVERTICILLATA.21EASTERNREDCEDAR- ‐JUNIPERUSVIRGINIANA.22NORTHERNBAYBERRY- ‐MYRICAPENSYLVANICA.24BLACKTUPELO- ‐NYSSASYLVATICA.26PITCHPINE- ‐PINUSRIGIDA.27EASTERNWHITEPINE- ‐PINUSSTROBUS.29BIGTOOTHASPEN- ‐POPULUSGRANDIDENTATA.312

QUAKINGASPEN- ‐POPULUSTREMULOIDES.32BLACKCHERRY- ‐PRUNUSSEROTINA.33WHITEOAK- ‐QUERCUSALBA.34BLACKOAK- ‐QUERCUSVELUTINA.35SWAMPAZALEA- ‐RHODODENDRONVISCOSUM.37PUSSYWILLOW- ‐SALIXDISCOLOR.38SASSAFRAS- ‐SASSAFRASALBIDUM.39BLUEBERRY- ‐VACCINIUMCORYMBOSUM.40NORTHERNARROWWOOD- 33

RedMapleȂAcerrubrumRed maple is one of themost common deciduous treeson campus where it grows 18-27meters tall. The oppositearrangement of the green,palmately veined, 3 lobed leavesdistinguishes red maple frommost other deciduous trees oncampus. On young trees the barkis silvery gray and smooth, butbecomes dark and rough withage. Despite its specific epithetof 'rubrum', meaning red, the redmaple is green most of thegrowing season. When withoutleaf, young twigs turn red in latewinter, and their color isespecially pronounced in earlyspring just prior to the flush ofnew spring growth. The budsand flowers are also a brilliantred at this time of year, and it is this late winter-early spring color on which the name 'red maple'is based. The red flowers of spring give way to paired, winged, green fruits, the samaras, duringearly summer.Few trees tolerate the range of soil conditions as can red maple. Most trees prefer eitherdry, damp, or wet soil conditions. Red maple is an exception; it has broad tolerance limits to soilmoisture. It occurs in swamps where it is referred to as 'swamp maple', but it also grows well indry upland areas.Red maple is one of the first trees to display red, orange, and yellow leaf colors in thefall. This brilliant fall color, its large stature, and its broad tolerance to varied environmentalconditions, has made red maple a favorite tree for landscaping.Acer rubrum is not to be confused with the 'Crimson King' or other varieties of Norwaymaple (Acer platanoides). The latter have maroon-red leaves throughout the growing season andare not native to New England woodlands. Some cultivated varieties of Japanese maple, (Acerpalmatum), may also have red leaves, but they are smaller trees with smaller more delicateleaves than Acer rubrum.4

Red maple is native to North America and occurs from Newfoundland to Florida, west toMinnesota and Texas. At UMD red maple is common throughout woodlands on campus,especially in low areas between the parking lots and Ring Road. Its fall color can best be viewedin early October around the small pond near the entrance to campus.5

YellowBirch- ‐BetulaluteaThe texture and odor of the bark ofthe yellow birch is helpful in identifyingthis tall tree of relatively undisturbedwoodlands. Like white birch, the barkpeels in horizontal bands or curls, and ithas a golden hue (almost like honey) andquite distinct from the white bark of whiteand gray birch. The bark has narrowhorizontal slits or lenticels that, when firstformed, allow for gas exchange. Thesimple, alternate, ovate leaves range insize from 7-11 cm long. Their margins aredoubly serrate and meet unequally at thepetiole.Yellow birch is monoecious withmale and female flowers occurring inseparate, elongate cone like structurescalled catkins. They form in the previousyear and remain tightly closed throughwinter to open in the following spring.Male catkins are 7-9 mm long with brownscales. The female catkins are larger(about 17 mm long) and are light reddishbrown with white hairs. The male catkinfalls off after it has shed its pollen but the female catkin persists as a small cone containing smallwinged nutlets which mature in August through October.Twigs are yellow brown to dark brown, and are smooth and shiny. Like the black birch,the twigs have a strong wintergreen flavor when broken. They can be made into a tea whensteeped in hot water. Sap can be collected in early spring and reduced by boiling to make syrup.Yellow birch may reach a height of 20-30 m, making it one of the tallest deciduous treesin New England. As lumber, it is the birch that is harvested the most, and it is used for finishwork in houses and in furniture. The curly peels of dry bark are useful tinder for startingcampfires.Yellow birch grows in rich soil in wet areas near swamps and streams. It is a tree oftenfound growing in dark woods in association with hemlock. These favored conditions of shade,moisture, and rich soil may restrict its range to undisturbed areas. Yellow birch is often found onthe sides of hills and ledges that have a northern exposure. Seedlings often sprout on dead6

stumps and in soil-moss pockets on top of large rocks. As they grow, their roots engulf thestumps and send roots over the rocks, a very characteristic growth form for this species.Yellow birch occurs from Newfoundland, west through the Great Lakes, and south toMaryland and at higher elevations in Tennessee. The favored environment of moist, shaded, richwoods restricts yellow birch on campus. There can be found numerous specimens growing withAmerican holly and Canadian hemlock in a relatively undisturbed wooded area between RingRoad and Cedar Dell Pond across from parking lots #13 and 14. Several also grow in the damparea behind the tennis courts.7

GrayBirch- ‐BetulapopulifoliaThe color and texture of thebark of gray birch are this tree's mostdistinctive features. It is white, likemany birches, but does not peel off incurls to the extent it does in white oryellow birch. At the base of thebranches, along the trunk, a black 'V'or chevron makes a distinctivepattern. Horizontal breaks (lenticels)occur on the bark and function in gasexchange. The bark of youngbranches is reddish-brown and turnswhite with age. The relatively small (5 cm wide by 7 cm long) triangularshaped leaves have doubly serratemargins and are distinct from themore oval shape of other localbirches. Gray birch is monoeciouswith separate, long-staminate andshort-pistillate catkins.Gray birch grows in standsalong the edges of woodlands and inopen areas. It is usually seen as asmall tree, seldom growing taller than4.5-6 m. A single plant may haveseveral main trunks.The bark of this and many other birches is elastic; it expands to accommodate increasesin girth from lateral growth. As a result of this elasticity the bark has a smooth surface, unlike thebark of most other kinds of mature trees. It is composed of many thin layers. The cells of theinner layers of bark contain tannic acid which gives newly exposed bark an orange color. Tannindoes not occur in the outer layers. Here the dead, empty cells reflect light similar to the waysnow reflects light, and the bark appears white.Gray birch reproduces by seeds which are dispersed by wind. This effective long distancedispersal strategy, together with its tolerance of sandy, dry soils enables gray birch to be one ofthe first colonizers of abandoned fields, disturbed soils, or burned-over areas. As such, gray birchis in early succession stages of forest development and is not usually a member of a climax forestcommunity. Reflecting its old field colonization it is sometimes called 'old field birch'.8

Gray birch occurs from southeastern Canada, south through New England to Virginia. Oncampus it grows along the edges of fields where its white bark is easily recognized. It isparticularly abundant along the outer edge of Ring Road near parking lots #2 and 9. Gray birch isoften identified incorrectly as a white birch (Betula papyrifera), but the latter has a morenortherly distribution and does not commonly grow out of cultivation in coastal southeasternMassachusetts.9

SweetPepperbush- ‐ClethraalnifoliaSweet pepperbush is a deciduousshrub that grows to 3 meters in height. It isone of the most common woody plantsaround campus woodlands where its denselybranched growth forms thickets. Threedistinctive characteristics of C. alnifolia areits persistent dry fruit capsules, true, nakedend buds, and its single bundle leaf scar. Thealternate, obovate to elliptical leaves are 510 cm long with an acute tip. Green aboveand pale below, the leaves have a sharplyserrated margin along their upper half. Theslender stems are similar in form and size tothose of mountain laurel and azaleas. Thetwigs are hairy and light brown when youngbut become smooth and gray to black withage.Young bark of the stems is brown,but turns grayish to black with age. Theflowers occur in terminal spike-like racemesor spikes which are 7.5-13 cm long.Individual white flowers, each calyx 05 cmacross, have 5 petals, 10 stamens, and adistinctive, persistent style that protrudesbeyond the stamens and petals from thecenter of the flower. In July and Augustsweet pepperbush blooms with an extremely strong fragrance. One of the easiest ways torecognize sweet pepperbush when not in flower is by its spikes of small round, woody capsules,each with its dried persistent stigma. Each fruit is only about 3 mm in diameter, but collectivelyin the raceme they are quite distinctive.Clethra alnifolia forms a dense, almost impenetrable border along the edges of wood lotsand ponds. Found in swamps and moist thickets it is a common wetland species. Because of itstolerance to wind-blown salt, sweet pepperbush is suited for landscaping along the coast.Sweet pepperbush occurs in coastal locations from southern Maine south to Florida andwest to eastern parts of Texas. As one of the most common shrubs on campus it can be foundalong the edges of most parking lots and wooded areas. Specimens also grow along the bordersof the wooded areas behind the Visual and Performing Arts Building.10

Sweetfern- ‐ComptoniaperegrineSweetfern is a small, woody,deciduous shrub approximately 0.5m high. Superficially this plant'sstature and foliage remind one of afern. The linear, pinnately lobedleaves offer a delicate fernlikeappearance. The leaves of sweetfernare very aromatic, and together withthe woody, persistent, erect stemsand small buds and flowers,distinguish this low shrubby plantfrom true ferns. Furthermore thestem of most true ferns is arhizome. Mature leaves ofsweetfern are somewhat rough andare 7- 15 cm long. They occuralternately along the stem, and havescalloped margins that curl towardsthe underside of the leaf. Theypersist through much of the winterbut by spring are gone before newleaves form. The buds have 4 ormore scales and the end buds arefalse. These characteristics, plus the aromatic nature of the twig, and leaf scars with 3 bundlescars, help identify sweetfern in winter.Sweetfern can be monoecious (as illustrated here) with separate male and female flowersoccurring on the the same plant, but most specimens are dioecious. Berries occur in fall on thefemale plants. The male flowers appear at the tip of the p