Oak-Pine-Northern Hardwood Forest Formation

152 / Wetland, Woodland, Wildland

Oak-Pine-Northern HardwoodForest FormationForests of Vermont’s Warmer Climate Areas

he Oak-Pine-Northern Hardwood Forest Formation is a group of forest typeswith affinities to forests of the so-called Central Hardwood Region, that part ofthe great Eastern Deciduous Forest that Braun (1950) describes as stretching

from Massachusetts and the lower Hudson Valley south to the mountains of Georgia.In the Central Hardwoods, oaks and hickories are common, along with tulip tree,beech, sugar maple, white ash, and formerly American chestnut.

Our Oak-Pine-Northern Hardwood Forest Formation is transitional in many waysbetween the Central Hardwoods and the Northern Hardwoods, and indeed this forma-tion is called “Transition Hardwood Forest” by the Society of American Foresters and bymany ecologists. Oaks, hickories, and pines mix in this formation with the ubiquitousnorthern hardwood species such as sugar maple, red maple, yellow birch, and beech.These forests are found in the warmer climate areas of Vermont: the Champlain Valley,the lower elevations of the Taconic Mountains, the Vermont Valley, and river valleys inthe Southern Vermont Piedmont. Certain tree species, such as chestnut oak, shagbarkhickory, and pitch pine, are restricted to this formation, while others, like northernwhite cedar, are actually more common in northern forests but find unusual niches herein this formation.

The Oak-Pine-Northern Hardwood Forest Formation is difficult to map on a broadscale: forests in this formation are sometimes found only locally as small patches withinNorthern Hardwood Forests. These small patches are common in the foothills of theChamplain Valley, for example, where Northern Hardwood Forest is the dominantcommunity, but where forests with more southern affinities occur on dry, south-facingslopes and ridgetops. The same phenomenon occurs in the Taconic Mountains and inthe Southern Vermont Piedmont.

In some areas of the state, however, the Oak-Pine-Northern Hardwood ForestFormation is dominant. The lower elevations of the Champlain Valley, though mostlyagricultural today, were probably dominated by Oak-Pine-Northern Hardwood Forestsprior to European settlement. Addison County in particular must have had large areas ofValley Clayplain Forest, while the sandy soils of Chittenden County had significant areasof Pine-Oak-Heath Sandplain Forest.

In spite of the name, Oak-Pine-Northern Hardwood Forest Formation, the communi-ties that make up this group are diverse in their species composition – not all have oaksas dominant species. Instead, they are held together as an ecological group becausethey all have species that occur in warmer climate areas, or in local situations wheresoil moisture is low, such as south-facing rocky ridges.

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Spruce-Fir Northern Hardwood Forest Formation / 153

Oak-Pine-Northern Hardwood Forest FormationNatural Communities

Read the four substrate headings and choose the substrate type that best matches thesite. Then read the short descriptions that follow and choose the community that fitsbest. Then go to the page indicated to confirm your decision.

�Substrate: Shallow-to-bedrock soils with deeper soils interspersed, often but notalways on ridgetops or knobs.

Red Pine Forest or Woodland: Maintained by fire, these small areas are dominatedby red pine, have very shallow soils, and have blueberries and huckleberries in theunderstory. They are widespread, and often surrounded by Northern Hardwood Forests.Go to page 155.

Pitch Pine-Oak-Heath Rocky Summit: These are fire-adapted communities on dry,acidic ridgetops where red oak, white oak, pitch pine, scrub oak, and white pine arecharacteristic trees. Heath shrubs are abundant. Go to page 158.

Limestone Bluff Cedar-Pine Forest: Northern white cedar dominates these areas ofshallow soils over calcareous bedrock. Red pine, white pine, hemlock and hardwoodsare also present. Characteristic herbs are ebony sedge and rock polypody. Go to page160.

Red Cedar Woodland: These are open glade-like communities on ledge crests,where red cedar is native and persistent, and grasses and sedges dominate the groundlayer. Go to page 163.

Dry Oak Woodland: These are very open areas with trees of low stature on dry,south facing hilltops. Grasses and Woodland sedge are dominant on the forest floor.Go to page 165.

Dry Oak Forest: These forests occur on rocky hilltops with very shallow, infertilesoils. Red oak, chestnut oak, white pine, and white oak can all be present; usually othertree species are absent. Heath shrubs dominate the understory. Go to page 167.

�Substrate: Mostly till-derived soils. Clay may be present, and bedrockexposures are found occasionally.

Dry Oak-Hickory-Hophornbeam Forest: These forests occur on till-derived soils,but they are often found on hilltops, and bedrock exposures are common. Soils arewell drained but are more fertile than in Dry Oak Forests. Red oak, sugar maple,hophornbeam, and shagbark hickory are variously dominant. Sometimes sugar mapleis the dominant tree, sometimes it is oak and hickory. Woodland sedge forms lawns.Go to page 169.

Mesic Maple-Ash-Hickory-Oak Forest: Sugar maple, white ash, hickories, andred and white oak are present in varying abundances. This community needs betterdocumentation. Go to page 171.

HOW TO IDENTIFY�

Oak-Pine-Northern Hardwood Forest Formation / 153


�Substrate: Soils that are mostly derived from lake or marine sediments, eitherclay or sand. Bedrock exposures may be found scattered within these areas.

Valley Clayplain Forest: Found on the clay soils of the Champlain Valley, this forestis variously dominated by white oak, swamp white oak, bur oak, hemlock, red maple,and shagbark hickory. Soils are poorly drained. Go to page 174.

White Pine-Red Oak-Black Oak Forest: These forests are found on coarse-texturedsoils. Red and black oak co-dominate along with white pine. Beech and hemlock arealso common. Heath shrubs are common in the understory. Go to page 177.

Pine-Oak-Heath Sandplain Forest: This is a rare community type, found on drysandy soils in warmer areas. Characteristic species are white pine, pitch pine, black oak,and red oak with an understory dominated by heath shrubs. Go to page 180.

�Substrate: Boulders or rock fragments on a steep slope.

Transition Hardwood Talus Woodland: These talus woodlands are found inwarmer areas, often on limestone but occasionally on slate, schist, granite, gneiss, orother rock. Some characteristic species are red oak, basswood, white ash, sweet birch,bitternut hickory, northern white cedar, hackberry, bulblet fern, and Canada yew.Go to page 184.

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DISTRIBUTION/ABUNDANCE

Small examplesare found locallyat low to moderateelevations(to 2,000 feet)throughout thestate, althoughthey are morefrequent in thenorthern half ofthe state.

ECOLOGY AND PHYSICAL SETTINGRed Pine Forests or Woodlands are

among Vermont’s most attractive naturalcommunities. Perched as they so oftenare on rocky ridgetops, surrounded byNorthern Hardwood Forest, they areespecially striking in autumn whencrimson huckleberry leaves make a sharpcontrast with the wintergreen’s shinyevergreen leaves and green pine needlesstand out against the surrounding orangeand yellow landscape.

Red Pine Forests or Woodlands areuncommon in Vermont and almostalways occur as very small patches in thelandscape. They are most common ondry rocky ridgetops or lake bluffs wherecompetition from other species is minimalbecause of fire, shallow soils, acidity, anddrought. Soils are usually shallowpodzols; bedrock is often exposed at thesurface. A few examples are known fromsandy glacial outwash areas in northeast-ern Vermont. In most cases in Vermont,Red Pine Forests or Woodlands arebelieved to be fire-maintained communi-ties. Without fire, many red pine standswould eventually succeed to more shade-tolerant species.

This community type does not fiteasily into the Oak-Pine-NorthernHardwood Forest Formation since itsdistribution has more to do with soilconditions than with climate. It is widelydistributed and occurs in some of thecolder areas of Vermont, including theNortheastern Highlands. It is included inthis formation because of its similarity toother communities treated here.

Red pine has been planted extensivelythroughout Vermont, and red pineplantations should not be confused withnatural Red Pine Forests or Woodlands.

VEGETATIONRed Pine Forests or Woodlands have

open to closed canopies dominated byred pine. Although forests and wood-lands are segregated and describedseparately in most places in this book, wecombine them here because red pineforests and red pine woodlands areusually intermixed at any given site, and

RED PINE FOREST OR WOODLAND



all red pine stands are so small thatdistinguishing between open and closedcanopy areas is impractical. Vegetation issimilar in both. Heath shrubs dominate theunderstory where soil is available. Wherebedrock is exposed or soil is very thin,mosses such as windswept moss andhaircap moss are common. Where thecanopy is dense, the understory vegetationtends to be sparse.

Red pine itself, the dominant species inthese forests, is especiallywell adapted to fire. Itsbark is thick and resistantto burning. It is notunusual to find two orthree separate fire scars,indicating different fires indifferent years, at the baseof a single red pine trunk.Red pine seeds germinatebest in a mineral soilseedbed, so a burnedridgetop provides a goodplace for the species to getestablished. And red pinecan withstand droughtmuch more effectivelythan most hardwoodspecies that wouldbecome established on arocky ridge, so over time itwill survive while species like red mapleand shagbark hickory will succumb tosevere droughts.

Red pines can reach ages of 275 years inVermont, but most trees are less than 120years old. In red pine stands that have beenstudied in northern Vermont, fires occurevery 20 to 100 or more years. These arethe times when seeds germinate and newpines become established.

ANIMALSMost examples of this community are

very small and are surrounded by NorthernHardwood Forest. The animals that occur inthat community travel through Red PineForests or Woodlands. Hermit thrushes canalmost always be heard in these forestsduring their breeding season.


SUCCESSIONAL TRENDSThis community is maintained by periodic

small wildfires. In the absence of fire, whitepine, red spruce, red oak, red maple, andbeech may become more abundant.

RELATED COMMUNITIESPitch Pine-Oak-Heath Rocky Summit:

This community is similar in soils andecological processes but is found in warmerclimate areas and is therefore dominated by

species with more southernaffinities, including pitch pineand scrub oak.

CONSERVATION STATUS

AND MANAGEMENT

CONSIDERATIONSA number of good

examples of this communityare found on public lands.On private lands, the greatestthreat may be fire suppres-sion. This threat grows asmore communications towersare built on rocky hilltops.

PLACES TO VISITRoy Mountain Wildlife

Management Area, Barnet.Vermont Department of Fish

and WildlifeBristol Cliffs, Bristol, Green Mountain

National ForestDeer Leap, Bristol, The Nature

Conservancy (TNC)Black Mountain Natural Area,

Dummerston, TNC

SELECTED REFERENCES AND FURTHER

READINGEngstrom, F. Brett. 1988. Fire ecology in

six red pine (Pinus resinosa Ait.) popula-tions in northwestern Vermont. Master ofScience project, University of Vermont.

Engstrom, F. Brett and Daniel H. Mann.1991. Fire ecology of red pine (Pinusresinosa) in northern Vermont, U.S.A.Canadian Journal of Forest Research21: 882-889

The thick patterned bark of redpine is resistant to fire.

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CHARACTERISTIC PLANTS


TREESAbundant SpeciesRed pine – Pinus resinosaOccasional to Locally Abundant SpeciesWhite pine – Pinus strobusRed maple – Acer rubrumBeech – Fagus grandifoliaRed spruce – Picea rubensPaper birch – Betula papyriferaRed oak – Quercus rubra

SHRUBSAbundant SpeciesBlack huckleberry – Gaylussacia baccataOccasional to Locally Abundant SpeciesShadbush – Amelanchier spp.Striped maple – Acer pensylvanicumLow sweet blueberry – Vacciniumangustifolium

Late low blueberry – Vaccinium pallidum

HERBSAbundant SpeciesWintergreen – Gaultheria procumbensOccasional to Locally Abundant SpeciesCanada mayflower – Maianthemumcanadense

Bracken fern – Pteridium aquilinumSarsaparilla – Aralia nudicaulisStarflower – Trientalis borealisTrailing arbutus – Epigaea repens

RARE AND UNCOMMON PLANTSDouglas’ knotweed – Polygonum douglasii



ECOLOGY AND PHYSICAL SETTINGPitch Pine-Oak-Heath Rocky Summits in southern

Vermont show a striking affinity to woodlands found insouthern and coastal New England, with their abundance ofpitch pine and the occasional appearance of more southernspecies such as scrub oak and mountain laurel. In otherrespects, especially in soil conditions and ecologicalprocesses, they are very much like Red Pine Woodlands.Pitch Pine-Oak-Heath Rocky Summits are restricted to dry,open, rocky ridges on acidic bedrock, in the warmer climateareas of the state. Fire almost certainly plays an importantrole in the maintenance of these communities and dry soilskeep many hardwood species from becoming established.

VEGETATIONThis community is a true woodland, with a canopy cover

of less than 60 percent and often closer to 30 percent. Treesare scattered and low growing. Pitch pine is the mostcommon tree. Red and white pine can be common as well,along with oak and red maple. The ground layer is oftenvery sparse, consisting of low grasses and forbs along withscattered low shrubs. Overall species diversity is very low,with heath shrubs dominating.

Pitch pine reaches its northern range limit in Vermontand is restricted almost exclusively here to Pitch Pine-Oak-Heath Rocky Summits and to Pine-Oak-Heath SandplainForest. It is a fire-adapted tree, with heat-resistant bark,seeds that germinate well on mineral soil rather than organicsoil, and cones that open when subjected to heat. It is alsoa drought-tolerant tree. This combination of attributes makesit successful in this community.

DISTRIBUTION/ABUNDANCERare statewide; known

only in Vernon, Dummerston,and Pownal in the extremesouthern part of the state, inWallingford in Rutland County,and in the Mount Moosalamooregion near Salisbury.

PITCH PINE-OAK-HEATH ROCKY SUMMIT

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PITCH PINE-OAK-HEATH ROCKY SUMMIT

ANIMALSSince this is a rare community in

Vermont, we have not studied its faunawell. Songbirds and mammals that arecommon in the adjacent forests, whetherthey are Northern Hardwood Forests, DryOak-Hickory Hophornbeam Forests, orRed Pine Woodlands, use this type ofcommunity as well.

SUCCESSIONAL TRENDSThese communities are maintained by

occasional fires that keep some deciduoustrees from becoming prominent.

VARIANTSNone recognized at this time.

RELATED COMMUNITIESRed Pine Forest or Woodland: This

community is similar ecologically but rarelyhas pitch pine or scrub oak.

CONSERVATION STATUS AND

MANAGEMENT CONSIDERATIONSThis is a fire-adapted community, so

natural fires should be allowed to burn onhilltops where this community occurs.

PLACES TO VISITBlack Mountain Natural Area, Dummerston.

The Nature Conservancy

TREESAbundant SpeciesPitch pine – Pinus rigidaWhite pine – Pinus strobusRed pine – Pinus resinosaRed oak – Quercus rubraRed maple – Acer rubrumOccasional to Locally Abundant SpeciesEastern hemlock – Tsuga canadensisPaper birch – Betula papyriferaGray birch – Betula populifoliaBlack oak – Quercus velutinaScrub oak – Quercus ilicifoliaAmerican beech – Fagus grandifolia

SHRUBSAbundant SpeciesLow sweet blueberry – Vacciniumangustifolium

Huckleberry – Gaylussacia baccataOccasional to Locally Abundant SpeciesWitch hazel – Hamamelis virginianaBlack chokeberry – Aronia melanocarpaLow red shadbush – Amelanchier sanguineaMountain laurel – Kalmia latifolia

HERBSAbundant SpeciesPoverty grass – Danthonia spicataOccasional to Locally Abundant SpeciesCanada mayflower – Maianthemum canadenseStarflower – Trientalis borealisSarsaparilla – Aralia nudicaulisHairgrass – Deschampsia flexuosa

RARE AND UNCOMMON PLANTSScrub oak – Quercus ilicifoliaMountain laurel – Kalmia latifolia

Scrub oak is rare in Vermont and is foundprimarily in the warm, dry, and shallow soils ofPitch Pine-Oak-Heath Rocky Summits.



ECOLOGY AND PHYSICAL SETTINGThese are dark, mostly coniferous forests dominated by

northern white cedar, which often has twisted or upswepttrunks. The community occurs on limestone or dolomitebluffs and outcrops or on outcrops of other calcareous rock.The most typical situations for this community type are therocky headlands of Lake Champlain. In these situations, thecommunity usually occupies a narrow band along the top ofthe bluff, although it may extend several hundred feet inland.Occasionally, these specialized forests occur away from thelake as well, on calcareous clifftops or ridges.

Cedars on these bluffs grow very slowly and are rarelystraight or tall. Growth rings are often less than 1/16 inchwide, in contrast to the normal rings of white pine, whichare up to 1/2 inch wide. On headlands in Malletts Bay,cedars reach ages of 300 years or more. In similar communi-ties on the Niagra Escarpment in Ontario, cedars exceeding1000 years in age have been documented.

Soils in Limestone Bluff Cedar-Pine Forests are veryshallow to nearly absent and have a high organic content.Because this soil does not hold moisture well and becauserainfall is naturally low in these places (less than 32 inches –low for Vermont), soils are very dry.

VEGETATIONSmall, twisted trees of northern white cedar are dominant

and provide dense shade along the edge of the cliff of bluff.Often the trees are no more than 20 feet tall. Red pine, whitepine, hophornbeam, and hemlock are other trees that arecommon here in varying amounts. Because of the denseshade, the understory is sparse and of low diversity, althoughhigh diversity forests can be close at hand. Ebony sedge isprobably the most characteristic herb of this community.

DISTRIBUTION/ABUNDANCERare statewide. Most

common on calcareous bluffsalong Lake Champlain, butthere are also small exampleson Lake Memphremagog.This community occurs onthe New York side of LakeChamplain as well, and likelyinto Québec. Very similarcommunities are found alongthe Niagra Escarpment inOntario.

LIMESTONE BLUFF CEDAR-PINE FOREST

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ANIMALSThe animals of these forests have not

been well studied.

SUCCESSIONAL TRENDSLimestone Bluff Cedar-Pine Forest is

believed to be the persistent communityon the limestone and dolomite bluffs ofLake Champlain, and our observationssuggest that the community replaces itselfalmost immediately when disturbed.Cedar regenerates well on open bedrock,whether the opening is natural or causedby humans.


RELATED COMMUNITIESTransition Hardwood Limestone

Forest, a variant of Mesic Maple-Ash-Hickory-Oak Forest: This communityis often found adjacent to LimestoneBluff Cedar Pine Forest, and grades into it.The two communities share many speciesin common.

Temperate CalcareousOutcrop Community: Smallopenings within LimestoneBluff Cedar Pine Forest arevery similar to TemperateCalcareous Outcrop, and thetwo communities share manyspecies in common.


MANAGEMENT CONSIDERATIONSThis is a rare community in Vermont,

and because it occurs on lake bluffs mostcommonly, it is vulnerable to clearing forviews and lake access, as well as to loggingnear the lake. It is also susceptible toencroachment by non-native exotic speciesalthough the impact of such encroachmentis unknown. Fortunately, some very fineexamples of this community are protectedon public and private conservation lands.Owners of bluffs where this communityoccurs can aid in its protection by keepingcutting of cedar to a minimum, by main-taining a natural forested buffer to thecommunity, and by removing invasiveexotic species such as buckthorn andhoneysuckle.

PLACES TO VISITKingsland Bay State Park, Ferrisburgh,

Vermont Department of Forests, Parksand Recreation.

Limestone Bluff Cedar-Pine Forest on the calcareous rockof Providence Island in Lake Champalin.




TREESAbundant SpeciesNorthern white cedar – Thuja occidentalisOccasional to Locally Abundant SpeciesWhite pine – Pinus strobusRed pine – Pinus resinosaEastern hemlock – Tsuga canadensisHophornbeam – Ostrya virginianaRed oak – Quercus rubraShagbark hickory – Carya ovataWhite ash – Fraxinus americanaSugar maple – Acer saccharumBasswood – Tilia americanaEastern red cedar – Juniperus virginiana

SHRUBSSnowberry – Symphoricarpos albusBush-honeysuckle – Diervilla lonicera

HERBSAbundant SpeciesEbony sedge – Carex eburneaHarebell – Campanula rotundifoliaWild columbine – Aquilegia canadensisRock polypody – Polypodium virginianumOccasional to Locally Abundant SpeciesIntermediate wood fern – Dryopteris intermediaMarginal wood fern – Dryopteris marginalis


NON-NATIVE PLANTSCanada bluegrass – Poa compressa

INVASIVE NON-NATIVE PLANTSMorrow’s honeysuckle – Lonicera morrowiiTartarian honeysuckle – Lonicera tataricaJapanese barberry – Berberis thunbergiiCommon buckthorn – Rhamnus catharticaEuropean buckthorn – Rhamnus frangula

RARE AND UNCOMMON PLANTSRam’s head lady’s-slipper – Cypripediumarietinum

Purple clematis – Clematis occidentalisFour-leaved milkweed – Asclepias quadrifoliaYellow oak – Quercus muehlenbergiiBuffalo-berry – Shepherdia canadensisWalking fern – Asplenium rhizophyllum

Ebony sedge – Carex eburnea

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RED CEDAR WOODLAND

ECOLOGY AND PHYSICAL SETTINGRed Cedar Woodlands are narrow areas of scattered trees

found on south or west facing clifftops in the warmer regionsof the state. The bedrock in these sites is usually not calcare-ous; schists and related rocks are the most common substrate.Soils are extremely shallow and well drained, and only themost drought-tolerant plants are able to persist under theseconditions. This community typically grades into Dry Oak-Hickory-Hophornbeam Forest or other dry oak-dominatedcommunities further back from the edge of the cliff.

VEGETATIONRed cedar dominates this sparse woodland community.

Red Cedar Woodland is the only community documented inVermont where red cedar maintains itself as a dominantspecies in a mid- to late-successional setting. (Interestingly,red cedar is an early-successional old field tree in many partsof the region, especially on clay soils and shallow-to-bedrocksoils of the Champlain Valley. These successional areas shouldnot be confused with Red Cedar Woodland.) The red cedarstypically hug the cliff edge and have windswept branches thatreflect the dominant wind direction. There is a sparse shrublayer. Grasses and other herbaceous plants, along withbryophytes and lichens, may be abundant between areas ofexposed bedrock.

ANIMALSWhere it occurs, eastern timber rattlesnake uses these

communities for basking.

DISTRIBUTION/ABUNDANCEThis community is found

on clifftops in the warmerregions of the state, includingthe Taconic Mountains, whereit is most abundant, theChamplain Valley, and theSouthern Vermont Piedmont.It is known from southernNew England as well. Sincethe conditions that supportthis community (exposedclifftops) usually occur assmall patches, examples ofRed Cedar Woodland arethemselves small and widelyscattered.




TREESAbundant SpeciesEastern red cedar – Juniperus virginianaHophornbeam – Ostrya virginianaOccasional to Locally Abundant SpeciesShagbark hickory – Carya ovataWhite pine – Pinus strobusRed oak – Quercus rubraRed pine – Pinus resinosaBlack cherry – Prunus serotinaWhite oak – Quercus albaChestnut oak – Quercus prinus

SHRUBSOccasional to Locally Abundant SpeciesDowny arrowwood – Viburnumrafinesquianum

Pasture rose – Rosa blandaLow red shadbush – Amelanchier sanguineaLow sweet blueberry – Vacciniumangustifolium

Choke cherry – Prunus virginiana

HERBSAbundant SpeciesWoodland sedge – Carex pensylvanicaPoverty grass – Danthonia spicataCow-wheat – Melampyrum lineareLittle bluestem – Schizachyrium scopariumSpreading dogbane – Apocynumandrosaemifolium

OCCASIONAL TO LOCALLYABUNDANT PLANTSField pussytoes – Antennarianeglecta

Rusty woodsia – Woodsiailvensis

Rock sandwort – Arenaria strictaCommon pinweed – Lecheaintermedia

Common woodrush – Luzulamultiflora

NON-NATIVE PLANTSCanada bluegrass – Poa compressaButter-and-eggs – Linaria vulgaris

RARE AND UNCOMMON PLANTSLongleaf bluet – Hedyotis longifolia(Houstonia longifolia)

Downy arrowwood – Viburnumrafinesquianum

Bronze sedge – Carex foenea

SUCCESSIONAL TRENDSIt is possible that fire plays a role in

maintaining these communities, but thisneeds investigation. It appears thatdroughty conditions are the major factorthat keeps these communities open andprevents shade-tolerant species frombecoming dominant.


RELATED COMMUNITIESTemperate Calcareous Outcrop:

Although Red Cedar Woodland is typicallynot found on calcareous bedrock, it canbe on circumneutral or mildly calcareousrock, and when it is, it can grade intoTemperate Calcareous Outcrop. The twocommunities share ecological attributes,such as droughty soils, and a few species,such as red cedar itself and downyarrowwood.


MANAGEMENT CONSIDERATIONSThis community is not especially

vulnerable to human-induced changesince it contains no marketable timber andis generally undevelopable. Owners ofthis natural community can protect it byallowing natural ecological processes totake place, including an occasional fire,and by refraining from cutting trees.

PLACES TO VISITHelen W. Buckner Memorial Preserve at

Bald Mountain, West Haven, TheNature Conservancy

RED CEDAR WOODLAND

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DRY OAK WOODLAND

ECOLOGY AND PHYSICAL SETTINGThese distinctive woodlands, sometimes referred to as

elfin oak woodlands, occur on south-facing upper hillslopesin southwestern Vermont. Soils are acidic, excessivelydrained silt loams with abundant rocky fragments. Thesewoodlands are southern in character with a prevalence ofoaks. The overstory oaks are short in stature, and thecrowns frequently appear gnarled. The trees are fartherapart than in typical forests, and the canopy is more open.Midstory or understory trees and shrubs are widely scat-tered. The ground flora is dominated by sedges, grasses,and heath shrubs, interspersed with oak seedlings, forbs,mosses, bedrock, and bare ground.

VEGETATIONThese woodlands are open and park-like, resembling

savannah. Trees are abnormally short, often half or less theheight they can reach in moist soils, and they are widelyscattered. Low shrubs such as huckleberry, low sweetblueberry, and the stoloniferous low red shadbush arepresent, but drought-tolerant sedges and grasses tend todominate the ground layer.

ANIMALSRing-neck snakes frequent these woodlands, often

spending days coiled beneath decaying wood. Uncommonbirds encountered in this woodland type may include tuftedtitmouse and yellow-billed cuckoo.

SUCCESSIONAL TRENDSIt is possible that fire plays a role in keeping these

woodlands open, but this needs verification.

DISTRIBUTION/ABUNDANCEThis community is rare

statewide. It is locallycommon in the hills of theTaconic Mountains, and thereare scattered occurrenceson Cheshire Quartzite in theChamplain Valley. Thesewoodlands are usually lessthan 20 acres in extent.




TREESAbundant SpeciesChestnut oak – Quercus prinusRed oak – Quercus rubraWhite oak – Quercus albaOccasional to Locally Abundant SpeciesRed pine – Pinus resinosaPitch pine – Pinus rigida

SHRUBSOccasional to Locally Abundant SpeciesLow red shadbush – Amelanchier sanguineaBlack huckleberry – Gaylussacia baccataLow sweet blueberry – Vacciniumangustifolium

Late low blueberry – Vaccinium pallidum

HERBSCommon SpeciesHairgrass – Deschampsia flexuosaWoodland sedge – Carex pensylvanicaCow-wheat – Melampyrum lineare

RARE AND UNCOMMON PLANTSRattlesnake-weed – Hieracium venosumSlender wheatgrass – Elymus trachycaulusDowny arrowwood – Viburnumrafinesquianum

Panicled tick trefoil – Desmodium paniculatumDouglas’ knotweed – Polygonum douglasiiForked chickweed – Paronychia canadensis


RELATED COMMUNITIESDry Oak Forest: A community with

similar species composition but with aclosed canopy and taller trees. Heathshrubs are more abundant in Dry OakForest.


MANAGEMENT CONSIDERATIONSThis is a rare and poorly understood

natural community, though threats to itare minimal. A few examples are protected.This community needs more study todetermine whether it is maintained byfire, and if so, whether prescribed fireshould be used to help maintain conservedexamples. Owners of hills where thisnatural community occurs can protect thecommunity by keeping hills free fromtowers and other structures so that naturalfires can burn without threatening humanproperty.

PLACES TO VISITNorth Pawlet Hills Natural Area, Pawlet,


DRY OAK WOODLAND

The deep, coarse furrows of chestnutoak bark are distinctive.

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DRY OAK FOREST

ECOLOGY AND PHYSICAL SETTINGThis community is found on rocky ridgetops of acidic or

circumneutral bedrock at low elevations. Most of the time, theyoccur as small patches within larger areas of Dry Oak-Hickory-Hophornbeam Forest or Northern Hardwood Forest, so theyprovide a welcome break from the ordinary when they areencountered after a hike up one of the hills or small mountainsof the Champlain Valley or Taconic Mountains.

In Dry Oak Forest, bedrock is close to the surface, soils aredry, and nutrients are limited. The low rainfall in the biophysi-cal regions where this community occurs, along with the lowmoisture-holding capacity of the soils, makes these very dryplaces. Fire may play a role in this community, but thispossibility needs more study. Gypsy moth can affect theseforests, as they thrive in oak forests.

VEGETATIONOverall diversity in these forests is quite low. Red oak and

white oak are mixed in the canopy, often with white pine.Chestnut oak can be abundant in southern regions. Heathshrubs dominate the understory, with huckleberry the mostabundant. Trees are poorly formed, but the canopy is nearlycontinuous.

ANIMALSDry Oak Forests are good habitat for turkey and grey

squirrel.

SUCCESSIONAL TRENDSWe know little about successional trends in this commu-

nity. Future studies should determine the role that fire playsin its maintenance.

DISTRIBUTION/ABUNDANCEDry Oak Forest is

occasionally found on acidicridgetops in the ChamplainValley and in the TaconicMountains. Similar communi-ties are found morecommonly to our southon rocky ridges. Black oakbecomes a common compo-nent of this communityfurther south; it is apparentlynot present, or at least notcommon, in the Vermontexamples.




TREESAbundant SpeciesRed oak – Quercus rubraWhite oak – Quercus albaOccasional to Locally Abundant SpeciesWhite pine – Pinus strobusChestnut oak – Quercus prinus

SHRUBSAbundant SpeciesHuckleberry – Gaylussacia baccataLow sweet blueberry – Vacciniumangustifolium

Occasional to Locally Abundant SpeciesFragrant sumac – Rhus aromaticaWitch hazel – Hamamelis virginiana

HERBSAbundant SpeciesPoverty grass – Danthonia spicataHairgrass – Deschampsia flexuosaOccasional to Locally Abundant SpeciesCow-wheat – Melampyrum lineareWhite snakeroot – Eupatorium rugosumWide-leaved sedge – Carex platyphyllaBottle-brush grass – Elymus hysterix

RARE AND UNCOMMON PLANTSRattlesnake-weed – Hieracium venosumSlender wheatgrass – Elymus trachycaulusDowny arrowwood – Viburnumrafinesquianum

Panicled tick trefoil – Desmodium paniculatumFour-leaved milkweed – Asclepias quadrifoliaSquawroot – Conopholis americana

DRY OAK FOREST


RELATED COMMUNITIESDry Oak-Hickory-Hophornbeam

Forest: Soils are perhaps more nutrientrich, and diversity is higher. Mapleand hickory are mixed in with the oaks.Chestnut oak is absent from thiscommunity.

Dry Oak Woodland: This communityis almost identical in terms of speciescomposition, but the increased droughti-ness of the soils reduces tree heightand canopy cover significantly.


MANAGEMENT CONSIDERATIONSThis community is somewhat uncom-

mon in Vermont, but a few good examplesare found on protected lands. Dry OakForests are not threatened by development,but logging may threaten some examples.

PLACES TO VISITSnake Mountain, Addison, Vermont

Department of Fish and WildlifeNorth Pawlet Hills Natural Area, Pawlet,


Hairgrass – Deschampsia flexuosa

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ECOLOGY AND PHYSICAL SETTINGThese are open, park-like forests where shrubs are sparse

and one can see a long distance through the woods. Suchopen forests are uncommon in Vermont, and most peoplewho visit them find them exceptionally beautiful. They arefound in the warmer parts of the state on hilltops or otherplaces where bedrock is close to the surface or is covered byshallow till. Warm climates combined with relatively shallowsoils contribute to droughty conditions. Trees do not grow aswell as they do on deeper, more fertile soils, and understoryvegetation is sparse. Many forests of this type are found onthe rocky portions of Champlain Valley farms. In most casesthey were never cleared for pasture or crops but were oftenused as woodland pasture. Both natural and anthropogenicdisturbances probably contribute to the structure of Dry Oak-Hickory-Hophornbeam Forests, but the relative importanceof each type of disturbance is difficult to know.

VEGETATIONThe canopy is somewhat open, and trees do not reach

great height. The shrub layer is very sparse. The ground layeris often dominated by lawns of woodland sedge, with otherherbs scattered about. In spite of the name of this commu-nity, sugar maple can be a canopy dominant, especially inareas of calcareous bedrock.

ANIMALSCommon mammals of these forests include white-tailed

deer and gray squirrel. Characteristic birds are white-breastednuthatch, scarlet tanager, and turkey. Rare reptiles includeblack rat snake, five-lined skink, and timber rattlesnake.

SUCCESSIONAL TRENDSWe know very little about successional trends in this

DISTRIBUTION/ABUNDANCEThis community has

southern affinities and isfound in the warmer parts ofVermont as well as in otherstates to our south and west.Most examples are in theChamplain Valley and TaconicMountains, although thecommunity is known from theSouthern Vermont Piedmontand on south-facing slopesin the Northern VermontPiedmont.

DRY OAK-HICKORY-HOPHORNBEAM FOREST




TREESAbundant SpeciesRed oak – Quercus rubraHophornbeam – Ostrya virginianaShagbark hickory – Carya ovataOccasional to Locally Abundant SpeciesWhite oak – Quercus albaSugar maple – Acer saccharumWhite ash – Fraxinus americana

SHRUBSOccasional to Locally Abundant SpeciesCanada honeysuckle – Lonicera canadensisMaple-leaf viburnum – Viburnum acerifolium

HERBSAbundant SpeciesWoodland sedge – Carex pensylvanicaOccasional to Locally Abundant SpeciesHog peanut – Amphicarpaea bracteataBottlebrush grass – Elymus hysterixBlue-stemmed goldenrod – Solidago caesiaPedunculate sedge – Carex pedunculataWide-leaved sedge – Carex platyphyllaWild oats – Uvularia sessilifoliaFurry brome – Bromus pubescensBlunt fescue – Festuca obtusaBroad-leaved ricegrass – Oryzopsis racemosa

RARE AND UNCOMMON PLANTSYellow oak – Quercus muehlenbergiiFour-leaved milkweed – Asclepias quadrifoliaWood lily – Lilium philadelphicumHitchcock’s sedge – Carex hitchcockianaForked chickweed – Paronychia canadensisAllegheny crowfoot – Ranunculusallegheniensis

Early blue violet – Viola palmataDeerberry – Vaccinium stamineumHound’s tongue – Cynoglossum borealeHairy honeysuckle – Lonicera hirsutaRue anemone – Anemonella thalictroidesBack’s sedge – Carex backiiSprout-bearing muhlenbergia – Muhlenbergiasobolifera

Slender-flowered muhlenbergia – Muhlenbergiatenuiflora

DRY OAK-HICKORY-HOPHORNBEAM FOREST

community. Sugar maple, oaks, hickory, andhophornbeam are all likely late-successionalcanopy components.

VARIANTSSugar Maple-Hophornbeam Forest:

This variant is found on calcareous soils.In structure, soil moisture, and dominantherbaceous plants it is like other DryOak-Hickory Hophornbeam Forests, butbecause of the more fertile soils, oak isuncommon and sugar maple is abundant.

RELATED COMMUNITIESDry Oak Forest: This is a forest type

that is more nutrient-poor or has bedrockcloser to the surface, or both. Red oak,white oak , and chestnut oak dominate, andheath shrubs are common in the groundlayer. Woodland sedge may be common inthese forests as it is in Dry Oak-Hickory-Hophornbeam Forest.

Mesic Maple-Ash-Hickory Forest:This forest type is found on lower slopes,where soils are deeper and moisture ismore available to plants. The two communi-ties often grade into each other.


MANAGEMENT CONSIDERATIONSDry Oak-Hickory-Hophornbeam Forest is

an uncommon community when the wholestate is considered, with only a handful ofextensive, natural examples known.Small patches of thiscommunity type aremoderately commonin the ChamplainValley.

PLACES TO VISITShaw Mountain

Natural Area,Benson,The NatureConservancy.

Woodland sedge –Carex pensylvanica

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ECOLOGY AND PHYSICAL SETTINGThese forests share much in common

with Northern Hardwood Forests, butthey have some striking affinities with theCentral Hardwood Forests of the Appala-chians to our south. Sugar maple, whiteash, and red maple are common trees,but more southern species, such as oaksand hickories, are present as well. Foundin the warmer climate areas of Vermont,these forests see higher-than-averagetemperatures and lower-than-averagerainfall. Mesic Maple-Ash-Hickory Forestshave soils that are typically somewhatdrier than those in the average NorthernHardwood Forest. These soils areprobably well drained to somewhatexcessively drained. Topography is gentleto rolling. Parent materials are glacial tills.Bedrock can be close to the surfacelocally, but shallow bedrock usuallycreates such extreme conditions thatother, drought-tolerant communitiesdevelop.

This is a poorly understood commu-nity in Vermont. More data on vegetation,soils, and land use history will help us tobetter understand the relationshipbetween these forests and others in thestate and region.

VEGETATIONThe variation in this community,

though poorly understood, is likely to beanalogous to the variation in NorthernHardwood Forests. Moister sites in covesand hollows will have higher productivityand a greater abundances of sugar mapleand white ash.

We can make some generalizationsabout vegetation, though. The canopytends to be a mix of northern hardwoodspecies such as beech, yellow birch,white ash, sugar maple, and red maple,with central hardwoods such as shagbarkhickory, bitternut hickory, pignut hickory,white oak, and red oak present in smallernumbers. The shrub layer in these forestsis sparse to well-developed, dependingon the light available. Herbs are low andrather sparsely distributed.


This is anuncommoncommunity inVermont, restrictedto mesic sites inthe ChamplainValley, TaconicMountains, andSouthern Piedmont.It has affinities withforest communitiesthat are morecommon to oursouth.

MESIC MAPLE-ASH-HICKORY-OAK FOREST




These forests can provide habitat forspecies that are common to our south,reaching their northern range limits insouthern Vermont. Examples includeflowering dogwood and round-leaved ticktrefoil. Tulip tree, the classic species of thecentral hardwoods, was reported growingin forests in the Connecticut Valley in the1940s, but it is unclear whether it wasgrowing naturally, or if it had been planted.Today there are no known native popula-tions of this tree.

ANIMALSThe mammal commu-

nity found in theseforests is probably quitesimilar to that found inNorthern HardwoodForests. White-tailed deerare common, and smallmammals include deermouse, white-footedmouse, woodlandjumping mouse, andchipmunk. Gray squirrelare more abundant herethan in NorthernHardwood Forests.Breeding songbirdsinclude eastern woodpewee, red-eyed vireo,ovenbird, black-throatedblue warbler, and scarlettanager. Turkeys are alsoabundant and rely on themast-producing treesfound in these forests.Amphibians and reptiles includeJefferson’s salamander, gray treefrog,four-toed salamander, and brown snake.

SUCCESSIONAL TRENDSWhite pine, paper birch, gray birch,

and bigtooth aspen are among the early-successional trees that can dominate theseforests following disturbance.

Throughout much of Vermont, we thinkof the oaks as early- to mid-successionalspecies, disappearing from forests wherethere is no natural or human disturbance,

such as fire or agriculture. In Mesic Maple-Ash-Hickory-Oak Forest, oak is probablymore persistent over time because itresponds well to the more droughtyconditions and warmer temperatures.White pine may also be a fairly persistentmember of this community.

VARIANTSTransition Hardwoods Limestone

Forest: This community is found in thewarm climate areas of Vermont, where

bedrock is calcareousand is close to the surface.The calcareous bedrockis expressed in thevegetation: typical herbsare bulblet fern, maiden-hair fern, white baneberry,blunt-lobed hepatica, wildginger, early meadow rue,large-flowered trillium,downy yellow violet,Dutchman’s breeches,wide-leaved sedge, andcommon sweet-cicely.There is much overlapbetween this communityand Rich NorthernHardwood Forest, butwarm-climate speciessuch as shagbark hickoryand an abundance ofoaks distinguish it.

Early-successionalvariants can be dominatedby white pine, paperbirch, gray birch, or

bigtooth aspen, or combinations of thesespecies.

RELATED COMMUNITIESDry Oak-Hickory-Hophornbeam

Forest: This is the closest relative to MesicMaple-Ash-Hickory-Oak Forest. It differs inbeing drier, and its overall range may belarger in Vermont.

Northern Hardwood Forest: This is aclosely related community, but in general itis moister and lacks the oaks and hickoriesthat are characteristic of Mesic Maple-Ash-Hickory-Oak Forest.

The smooth, gray bark of youngshagbark hickory quickly developsinto the shaggy, long, curling platesthat give this tree its name.

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Mesic Red Oak-Hardwood Forest:This is also quite similar, but again lacksthe hickories and other southern species.

Limestone Bluff Cedar-Pine Forest:This community occurs adjacent to theTransition Hardwoods Limestone Forestvariant of Mesic Maple-Ash-Hickory-OakForest. The two communities share severalspecies in common, but northern whitecedar dominates limestone Bluff Cedar-Pine Forest.


MANAGEMENT CONSIDERATIONSThe distribution of this community is

poorly known, and therefore its conserva-tion status is unclear. A few examples areknown on public land.

PLACES TO VISITBomoseen State Park, Castleton. Vermont

Department of Forests, Parks, andRecreation

TREESOccasional to Locally Abundant SpeciesRed oak – Quercus rubraWhite oak – Quercus albaRed maple – Acer rubrumSugar maple – Acer saccharumEastern hemlock – Tsuga canadensisWhite pine – Pinus strobusPaper birch – Betula papyriferaShagbark hickory – Carya ovataHophornbeam – Ostrya virginianaWhite ash – Fraxinus americanaBasswood – Tilia americana

SHRUBSMaple-leaf viburnum – Viburnum acerifoliumShadbush – Amelanchier spp.Striped maple – Acer pensylvanicumWitch hazel – Hamamelis virginiana

HERBSMarginal wood fern – Dryopteris marginalisWhite snakeroot – Eupatorium rugosumCommon sweet-cicely – Osmorhiza claytoniiLarge-flowered trillium – Trillium grandiflorum


RARE AND UNCOMMON PLANTSPignut hickory – Carya glabraFlowering dogwood – Cornus floridaRound-leaved tick trefoil – Desmodiumrotundifolium

Minnesota sedge – Carex albursinaFour-leaved milkweed – Asclepias quadrifoliaSquawroot – Conopholis americanaHandsome sedge – Carex formosaYellow oak – Quercus muehlenbergiiBroad beech fern – Thelypteris hexagonopteraHitchcock’s sedge – Carex hitchcockianaSpicebush – Lindera benzoinPerfoliate bellwort – Uvularia perfoliataShort-styled snakeroot – Sanicula canadensis



ECOLOGY AND PHYSICAL SETTINGThis is the forest that dominated the clay and silt soils of

the Champlain Valley prior to European settlement and thesubsequent conversion of forest to agricultural land. Todaythis forest community is extremely rare. The clay soils weredeposited in the Champlain Valley during and following thePleistocene glaciation, both when the valley was flooded bya large freshwater lake, and later when salt water invadedthe basin from the north. The soils are deep and fertile,and make ideal agricultural soils, especially when drained.Moisture in these soils varies with soil texture and topo-graphic position, and the most well drained areas were theones preferentially cleared for agriculture. The ValleyClayplain Forest remnants that are left are generally on themoister sites, though they typically contain a mosaic of wetand less-wet areas. In some areas, thin lenses of sand lieover the clay. It is unknown how these areas differ fromplaces without sand. Lapin (1998) described ClayplainForests and the variations within them, and much of thisinformation is taken from his study.

This natural community is a mesic, or less wet, clayplainforest. Wet Clayplain Forest is considered a variant and istypically a wetland community. These two variants arefound together, however, and from a practical standpointare difficult to separate. Mesic Clayplain Forest has moder-ately well drained to somewhat poorly drained soils butpools and wet hollows (Wet Clayplain Forest) are scatteredthroughout. In both, soil fertility is high. Because of the wetsoils, trees are typically shallow-rooted and are easily blownover during heavy winds. Tip-up mounds are therefore acommon sight in these forests.

DISTRIBUTION/ABUNDANCEThis community is known

from the Champlain Valleyof Vermont, and perhapsNew York and Québec. It isunknown whether it occursto the west in the clay soilsadjacent to the Great Lakes.

VALLEY CLAYPLAIN FOREST

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VEGETATIONThe canopy in Clayplain Forests is a

diverse mixture of trees, including mostcommonly white oak, red oak, red maple,white pine, shagbark hickory, and whiteash. Associated species include hemlock,sugar maple, beech, swamp white oak, andbur oak. The shrub layer is typically welldeveloped, and the herb layer can be quitedense and very diverse. Characteristicspecies include barren strawberry andgrove sandwort. Slight changes inmicrotopography yield changes in speciescomposition. Mounds within level sites mayhave dry-site species such as low sweetblueberry and woodland sedge, whilehollows harborwet site speciessuch as winter-berry holly andBailey’s sedge.

ANIMALSCharacteristic

mammals in thiscommunity aregray squirrel,eastern chipmunk,beaver (in wetareas), raccoon,and the ubiquitouswhite-tailed deer.Common birds are wood thrush, easternwood pewee, ovenbird, northern oriole,and downy woodpecker. Typical amphib-ians are blue spotted salamander, Americantoad, wood frog, and grey treefrog. In thevernal pools within these forests, one canfind caddis flies, predaceous diving beetles,and horsehair worms.

SUCCESSIONAL TRENDSWhite pine seems to dominate some

early-successional areas. Green ash andquaking aspen are also common early-successional species, along with eastern redcedar, red maple, bur oak, and white ash.

VARIANTSWet Clayplain Forest: This variant has

soils that are somewhat poorly to poorlydrained and is classified as a wetland. It is

found as small to medium-sized inclusionswithin the Mesic Clayplain Forest and is veryclosely allied with it, hence its inclusion here.The canopy is dominated by swamp whiteoak, red maple, and green ash or white ash.White oak, shagbark hickory, white pine,American elm, and black ash are also present.Musclewood is the dominant small tree. Theshrub layer is dense, and wetland plants suchas sensitive fern, water hemlock, and waterhorehound are present along with the sedgeslisted above.

RELATED COMMUNITIESMesic Maple-Ash-Hickory-Oak Forest:

This forest type is found on non-clay soils inthe warm climateregions of the stateand shares manyspecies in commonwith the drierexamples ofClayplain Forest.

CONSERVATION

STATUS AND

MANAGEMENT

CONSIDERATIONSThis is certainly

one of the mostseverely altered

communities in Vermont. Its present size isa small fraction of its presettlement extent,and the exact nature and composition ofthe presettlement Clayplain Forest are notknown. The remaining examples are allunder one hundred acres and are separatedfrom one another by large areas of agricul-tural land, making plant and animal dispersalbetween sites very difficult. A few goodexamples are protected on state and privateconservation lands, but the remainingexamples need protection badly. The long-term protection of the clayplain landscapewill require not only protection of theremaining examples but also restorationof some agricultural land back to ClayplainForest, an exciting and challengingproposition.

The small yellow flowers of barren strawberry are acommon spring sight in Valley Clayplain Forests.




PLANTS OF MESIC CLAYPLAINFOREST

TREESCommon SpeciesWhite oak – Quercus albaRed oak – Quercus rubraRed maple – Acer rubrumShagbark hickory – Carya ovataWhite pine – Pinus strobusOccasional to Locally Abundant SpeciesSwamp white oak – Quercus bicolorBur oak – Quercus macrocarpaWhite ash – Fraxinus americanaSugar maple – Acer saccharumEastern hemlock – Tsuga canadensisBasswood – Tilia americanaHophornbeam – Ostrya virginianaAmerican Beech – Fagus grandifoliaMusclewood – Carpinus caroliniana

SHRUBSCommon SpeciesMaple-leaf viburnum – Viburnum acerifoliumCarolina rose – Rosa carolinaWitch hazel – Hamamelis virginianaOccasional to Locally Abundant SpeciesLow sweet blueberry – Vacciniumangustifolium

HERBS AND TRAILING SHRUBSBarren strawberry – Waldsteinia fragarioidesGrove sandwort – Arenaria laterifloraWild oats – Uvularia sessilifoliaWild geranium – Geranium maculatumBearded shorthusk – Brachyelytrum erectumLarge enchanter’s nightshade – Circaealutetiana

Graceful sedge – Carex gracillimaLoose sedge – Carex laxiculmisRosy sedge – Carex roseaWoodland sedge – Carex pensylvanicaDwarf raspberry – Rubus pubescensSwamp dewberry – Rubus hispidus

PLANTS OF WET CLAYPLAIN FOREST

TREESSwamp white oak – Quercus bicolorAmerican elm – Ulmus americanaBur oak – Quercus macrocarpa

SHRUBSWinterberry holly – Ilex verticillataNorthern arrowwood – Viburnum dentatum var.lucidulum

HERBSLakeshore sedge – Carex lacustrisSlender sedge – Carex teneraSwollen sedge – Carex intumescensBlunt broom sedge – Carex tribuloidesMarsh fern – Thelypteris palustrisBailey’s sedge – Carex baileyi


RARE AND UNCOMMON PLANTSShort-styled snakeroot – Sanicula canadensisHarsh sunflower – Helianthus strumosusBuxbaum’s sedge – Carex buxbaumiiLeafy bulrush – Scirpus polyphyllusGrove sandwort – Arenaria laterifloraLoose sedge – Carex laxiculmisYellow bartonia – Bartonia virginicaAmerican hazelnut – Corylus americanaDrooping bluegrass – Poa saltuensisUmbellate sedge – Carex umbellataRough avens – Geum laciniatumBroad beech fern – Thelypteris hexagonopteraMinnesota sedge – Carex albursinaGray’s sedge – Carex grayiFolliculate sedge – Carex folliculataHandsome sedge – Carex formosaStout woodreed – Cinna arundinaceaFragrant sumac – Rhus aromaticaSpicebush – Lindera benzoin


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WHITE PINE-RED OAK-BLACK OAK FOREST

ECOLOGY AND PHYSICAL SETTINGSouthern New England is the real

home of this community. Oaks and pinesare the dominant vegetation in much ofeastern Massachusetts and southern NewHampshire, where glacial outwashprevails and where historically land usehas had a significant impact on theforests. The parts of Vermont that haveaffinities with those places are where weare likely to find White Pine-Red Oak-Black Oak Forest.

Both red oak and white pine, thedominant species in this forest, do best inwell-drained soils where the climate ismore temperate than boreal. For Vermont,this means the Champlain Valley and theSouthern Vermont Piedmont – especiallythe Connecticut Valley. In these parts ofthe state, the growing season is 130 daysor more and the average annual rainfalldoes not exceed 42 inches or so. Theseare also regions where coarse outwashsoils are common. Similar conditions canbe found in the Taconic Mountains andVermont Valley, too, and in river valleysthat penetrate other biophysical regions.In general, though, this community is notfound above 1,400 feet in elevation. Soilsare well drained to excessively welldrained, and parent materials are eitheroutwash or shallow till over bedrock.

VEGETATIONWe have no known undisturbed

examples of this forest type, so it isdifficult to fully understand its naturalvegetation. But historical informationtogether with our studies of someyounger examples suggest that matureWhite Pine-Red Oak-Black Oak Forestswill have white pine, red oak, black oak,red maple, and hemlock as commonmembers of the canopy. The shrub layeris a mixture of tall shrubs like witch hazeland smooth shadbush, and low shrubs ofthe heath family. Herbs are sparse, andoverall plant diversity is low.


White Pine-Red Oak-BlackOak Forest isan uncommoncommunity inVermont, foundonly in the warmestclimate areas andon coarse orshallow-to-bedrock,well-drained soils.

This communityis common to oursouth.



ANIMALSThe animals of this natural community

have not been well studied, but mammalsthat are commonly seen include white-tailed deer, gray squirrel, and easternchipmunk.

SUCCESSIONAL TRENDSWhen we see white pine and red oak,

we tend to think about land use history anddisturbance. Both species do well indisturbed areas such as old fields andlogged lands. So one always needs to askwhether this community will persist wherewe see it today, or whether it will bereplaced over time by more stable species,such as hemlock or beech. This is a site-by-site question: we cannot generalize. Thereare places where oak and/or pine dominatenow because of past disturbance, but willbe replaced over time if natural or humandisturbance is absent. In other places, thetwo species “trade places” in the canopyover time — oak dominating for a numberof decades, to be replaced by pine thatpersists for a few more, giving way onceagain to oak. This situation may go on for avery long time if soil and climate conditionsare right, and in these cases we considerWhite Pine-Red Oak-Black Oak Forest to bethe stable natural community for the site.

Fire may play a role in the maintenanceof this community, but we know little aboutthe historical role of fire.

Where White Pine-Red Oak-Black OakForest is the natural community, naturaldisturbances such as fire and wind stormscan change the species compositiontemporarily. Common early-successionalspecies are gray birch, paper birch, blackcherry, aspen, hophornbeam, sweet birchand white pine.


RELATED COMMUNITIESPine-Oak-Heath Sandplain Forest:

This community is very closely related toWhite Pine-Red Oak-Black Oak Forest. Themain difference is soil moisture. Pine-Oak-Heath Sandplain Forest occupies drier siteswithin large areas of deltaic sand deposits,while White Pine-Red Oak-Black OakForest is on slightly moister – though stillwell drained – sites. The two communitiesare thus often juxtaposed and inte-fingering. A sandplain that is incised bystreams, for example, may have Pine-Oak-Heath Sandplain on the level plains andWhite Pine-Red Oak-Black Oak Forest onthe slopes of the stream valleys.


MANAGEMENT CONSIDERATIONSWe know of no mature examples of this

community. A few examples are conservedon protected lands. Because this is anuncommon and restricted community,mature examples should be sought and afew protected by conservation easements.Timber management should considernatural ecological processes and shouldencourage the regeneration of the speciesthat would naturally grow on these sites.

PLACES TO VISITCentennial Woods, Burlington, University

of VermontSunny Hollow Natural Area, Colchester,

Town of ColchesterBellows Falls Village Forest, Rockingham,

Town of RockinghamWilgus State Park, Weathersfield, Vermont

Department of Forests, Parks, andRecreation


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TREESCommon SpeciesWhite pine – Pinus strobusBlack oak – Quercus velutinaRed oak – Quercus rubraOccasional to Locally Abundant SpeciesWhite oak – Quercus albaEastern hemlock – Tsuga canadensisRed maple – Acer rubrumWhite ash – Fraxinus americanaRed pine – Pinus resinosaAmerican beech – Fagus grandifolia

SHRUBSCommon SpeciesWitch hazel – Hamamelis virginianaBeaked hazelnut – Corylus cornutaSmooth shadbush – Amelanchier laevisMaple-leaf viburnum – Viburnum acerifoliumOccasional to Locally Abundant SpeciesLow sweet blueberry – Vacciniumangustifolium

Late low blueberry – Vaccinium palladiumSheep laurel – Kalmia angustifoliaMountain laurel – Kalmia latifolia

Sarsaparilla – Aralia nudicaulis


HERBSCommon SpeciesStarflower – Trientalis borealisSarsaparilla – Aralia nudicaulisCanada mayflower – Maianthemum canadenseWoodland sedge – Carex pensylvanicaBracken fern – Pteridium aquilinumOccasional to Locally Abundant SpeciesWintergreen – Gaultheria procumbensPipsissewa – Chimaphila umbellataRunning pine – Lycopodium clavatumPink lady’s slipper – Cypripedium acauleSpotted wintergreen – Chimaphila maculata

INVASIVE NON-NATIVE PLANTSNorway maple – Acer platanoidesMorrow’s honeysuckle – Lonicera morrowiiEuropean buckthorn – Rhamnus frangula

RARE AND UNCOMMON PLANTSScarlet oak – Quercus coccineaSlender mountain-rice – Oryzopsis pungensYellow panic grass – Panicum xanthophysumMountain laurel – Kalmia latifoliaSpotted wintergreen – Chimaphila maculata


ECOLOGY AND PHYSICAL SETTINGPine-Oak-Heath Sandplain Forests are one of Vermont’s

rarest – and certainly one of its most threatened –communities. Soils in this community are well drained toexcessively well drained sands, varying locally in coarsenessand moisture holding capacity. They are acidic andnutrient-poor. The Champlain Valley sands were depositedpostglacially, as large, sediment-filled rivers of glacialmeltwater emptied into glacial Lake Vermont or, later,into the Champlain Sea. Where the rivers entered the lakeor sea, coarse sediments were deposited first, in greatfan-shaped deltas. These deltas form our present-daysandplains, primarily near the mouths of the Winooski,Lamoille, and Missisquoi Rivers. Similar events took placein the Connecticut Valley, though on a smaller scale.

The present-day deltas are incised by small streams, andso are complex areas of flat terrain cut by deep gullies.The flat areas have the best Pine-Oak-Heath SandplainForests, but locally low areas, even on the tops of the deltas,can be quite moist or even wet, supporting red mapleswamps, vernal pools, or small open wetlands. The slopesof the gullies are often slightly moister than the generallydry tops and therefore support White Pine-Red Oak-BlackOak Forest. The nature of the gully bottoms depends on thelocal soil conditions. Often clay underlies sand and isexposed near gully bottoms, supporting moist forests orwetlands. Underlying bedrock can influence vegetation, too,although its effect is usually masked by the sand above it,which can be more than 30 feet deep.

Like the larger pine barrens of Albany, New York, andConcord, New Hampshire, these forests are fire-adaptedcommunities. Ours are not, however, true pine barrens: theyprobably never had extensive open areas with stunted treesand parched windblown sand, as true pine barrens have.

PINE-OAK-HEATH SANDPLAIN FOREST

DISTRIBUTION/ABUNDANCEIn Vermont, this commu-

nity is restricted to sandsin the warmer biophysicalregions: the Champlain Valleyand the Southern VermontPiedmont. The most signifi-cant areas of Pine-Oak-HeathSandplain Forest are inwestern Chittenden County,on the state’s largest sanddeposits, but small remnantsites are found in theConnecticut River valley inWindsor and WindhamCounties.

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But Vermont’s sandplains almost certainlyburned occasionally prior to Europeansettlement, and likely had more of a“barrens” feel then. Pitch pine, one of theimportant components of this community,is especially well adapted to fire. Its barkprotects the trees from light fires that cankill other species. Additionally, pitch pineseeds germinate most successfully in thebare mineral soil that is left after a fireburns away the leaf litter. Other plantsprobably benefited from the natural fires,too. A number of the rare and uncommonplants of this community require open, dryareas that would be common where fireswere frequent. Ecologists believe that firewas important in Vermont’s sandplains andthat these communities have, in the lasttwo centuries, lost much of their originalcharacter as a consequence of fire suppres-sion and development.

VEGETATIONThe canopy in these forests is fairly

open. Pitch pine, red maple, and black oakare the most common canopy species. Tallshrubs are scattered. The ground layer isoften very sparse, composed of low herbsand scattered low shrubs, most of themmembers of the heath family. Heaths as agroup are especially well adapted to acidicconditions. Overall plant diversity is low,although Pine-Oak-Heath Sandplain Forestshave a disproportionately high number ofrare species, perhaps more than any othernatural community. Many of these speciesare at their range limits in Vermont and aremore common elsewhere. The warmclimate and sunny openings of oursandplains provide good habitat for them.

ANIMALSPine warbler is a characteristic breeding

bird in this community. The most character-istic fauna are invertebrates.

SUCCESSIONAL TRENDSWhen fire and other disturbances are

absent from this community for a time,the duff layer will build up. Under theseconditions, pitch pine seeds are inhibitedfrom germinating while other speciesgerminate and persist. Thus pitch pineis likely to decrease in importance, thecanopy is likely to become more closed,and hemlock, white pine, red oak, blackoak, and red maple are likely to becomemore abundant, with hemlock and whitepine ultimately becoming most abundant.The many rare plants that rely on openingsare likely to decrease in number as well.Presettlement Pine-Oak-Heath SandplainForests had occasional openings, and somepitch pine, but white pine was probablymore abundant.


RELATED COMMUNITIESWhite Pine-Red Oak-Black Oak

Forest: This community is very similar toPine-Oak-Heath Sandplain Forest, but itssoils are less dry. Trees therefore growtaller and form a more closed canopy, andopenings are less frequent. Fire can play arole in both communities, however. WhitePine-Red Oak-Black Oak Forest is oftenfound associated with Pine-Oak HeathSandplain Forest in slightly moister areassuch as slopes and low areas.


MANAGEMENT CONSIDERATIONSPine-Oak-Heath Sandplain Forest is a

very threatened community in Vermont.With their deep, well-drained soils, areasoccupied by this community are in greatdemand for residential and industrialdevelopment, as well as for sand extraction.Of the original acreage in ChittendenCounty prior to European settlement –estimated at 15,000 acres based on thepresence of suitable soils – we now haveonly about 650 acres, or about 4.5 percentof the original total. Much of the rest hasbeen converted to housing developments,




Fires have been purposely ignited in some controlled settings to study the effects of this natural disturbanceof Pine-Oak-Heath Sandplain Forest.

airports, commercial areas, pine plantations,and agricultural fields. One very smallexample of this natural community is in atown park, and another much largerexample is under excellent ecologicalmanagement, including the use of pre-scribed fire. No example has permanentlegal protection.

Owners of good examples of this naturalcommunity can help maintain them byallowing natural ecological processes tofunction and by encouraging the growth ofpitch pine and other species that are nativeto the community.

PLACES TO VISITSunny Hollow Natural Area, Colchester,

Town of Colchester


SELECTED REFERENCES AND FURTHER

READINGSHowe, C.D. 1910. The reforestation of sand

plains in Vermont: A study in succession.Botanical Gazette 49:126-149

Siccama, Thomas G. 1971. Presettlementand present forest vegetation in northernVermont with special reference toChittenden County. American MidlandNaturalist 85:153-172

Engstrom, F. Brett. 1991. Sandplain naturalcommunities of Chittenden County,Vermont: A report to the VermontDepartment of Fish and Wildlifeconcerning the management andviability of a threatened habitat inVermont. Vermont Nongame andNatural Heritage Program.

Profile / 183


TREESCommon SpeciesPitch pine – Pinus rigidaWhite pine – Pinus strobusBlack oak – Quercus velutinaRed oak – Quercus rubraRed maple – Acer rubrumOccasional to Locally Abundant SpeciesPaper birch – Betula papyriferaGray birch – Betula populifoliaAmerican beech – Fagus grandifolia

SHRUBSCommon SpeciesLow sweet blueberry – Vacciniumangustifolium

Late low blueberry – Vaccinium pallidumBlack huckleberry – Gaylussacia baccataWitch hazel – Hamamelis virginianaSmooth shadbush – Amelanchier laevisBeaked hazelnut – Corylus cornutaSheep laurel – Kalmia angustifoliaSweetfern – Comptonia peregrina

HERBSAbundant SpeciesCanada mayflower – Maianthemum canadenseSarsaparilla – Aralia nudicaulisBracken fern – Pteridium aquilinumWintergreen – Gaultheria procumbensOccasional to Locally Abundant SpeciesStarflower – Trientalis borealisWhorled loosestrife – Lysimachia quadrifoliaPink lady’s slipper – Cypripedium acauleBastard toadflax – Comandra umbellataCow-wheat – Melampyrum linearePipsissewa – Chimaphila umbellata

RARE AND UNCOMMON PLANTSYellow panic grass – Panicum xanthophysumBlunt-leaved milkweed – Asclepiasamplexicaulis

Hairy lettuce – Lactuca hirsutaPlains frostweed – Helianthemum bicknelliiHoughton’s cyperus – Cyperus houghtoniiLow bindweed – Calystegia spithameaCanada frostweed – Helianthemum canadenseHarsh sunflower – Helianthus strumosusWild lupine – Lupinus perennisSlender mountain-rice – Oryzopsis pungensHay sedge – Carex siccataMuhlenberg’s sedge – Carex muhlenbergiiLarge whorled pogonia – Isotria verticillataSweet goldenrod – Solidago odoraLong-spiked three-awn – Aristida longespicaYellow wild-indigo – Baptisia tinctoriaSilver-flowered sedge – Carex argyranthaFernald’s sedge – Carex meritt-fernaldiiWild sensitive plant – Chamaecrista nictitansLace love-grass – Eragrostis capillarisFew-flowered panic grass – Panicumoligosanthes

Racemed milkwort – Polygala polygamaWhorled milkwort – Polygala verticillataSlender knotweed – Polygonum tenueScarlet oak – Quercus coccineaWood lily – Lilium philadelphicum




ECOLOGY AND PHYSICAL SETTINGIn the agricultural landscape of

lowland Vermont, these places are wildhavens of jumbled rocks, dense shrubs,rare ferns, odd trees, and fascinatingwildlife. Although they tend to be small(less than 10 acres in most cases) and areoften near agricultural areas, they canseem very far away from the cultivatedlandscape, because with their unstablerocky soils, they have nearly always beenleft alone by farmers, sheep, cows, andloggers.

Transition Hardwood Talus Woodlandsare rockfall slopes below cliffs in thewarmer regions of the state. They are asvariable as the bedrock of those regions,but they share in common a speciescomposition that reflects their relativelywarm climate. The rock that makes upthe talus has moved downslope from thecliffs above, and the size and shape ofthe boulders reflects the nature of thebedrock making up the cliff. Limestone,dolomite, and marble usually break intofairly large blocky fragments but weathereasily, allowing soil to form between therocks over time. The rocks tend to bemore or less stable once they are inplace, and when weathered they producenutrient-rich soils. Shale and slate breakinto platy fragments that are small andinherently unstable, and producenutrient-poor, droughty soils. Gneiss,granite, and acidic quartzite break intolarge fragments that are stable once theyare in place and do not weather easily.Open talus is common where these rocktypes are prominent. Schists and phyllitesare variable, sometimes behaving likeslate and shale, other times behavingmore like limestone.

VEGETATIONVegetation in Transition Hardwood

Talus Woodlands varies with the natureof the bedrock. Although the communityis a woodland, meaning it has a canopycover of less than 60 percent, there arelocal areas where the canopy is moredense, so technically forest and wood-land are intermixed. Because all occur-rences of this community are small,

TRANSITION HARDWOOD TALUS WOODLAND


Uncommonin Vermont,restricted to thewarm climateareas of the state.

Profile / 185


making the distinction is sometimesimpractical and is usually not necessaryfrom a management perspective.

Many of these woodlands are character-ized by an unusual diversity of trees,some of which are nearly restricted to thiscommunity type, a dense and diverseshrub layer, and a high diversity of herba-ceous species, including many rare species.Spring wildflowers and ferns are especiallyabundant.

Transition Hardwood Talus Woodlandsare curiously like some floodplain forests inthat they share a few key species. Hack-berry and bladdernut are two species thatshare these two communities – and almostno others – in common. The similarity mustlie in the continual input of new soil andnutrients, in one case as a result of colluvialprocess, in the other as a result of alluvialprocesses.

ANIMALSBlack rat snake, a rare animal in

Vermont, lives and breeds in this commu-nity along with the common garter snake.Other animals of this community needfurther study.

SUCCESSIONAL TRENDSSlope instability and downslope

movement are the processes that createand maintain openings in this community.Canopy gaps and slides create local areasof early-successional habitat, wheremountain maple and other species thatdo well in disturbed areas can thrive.

VARIANTSTransition Hardwood Limestone

Talus Woodland: These woodlands arefound on limestone, dolomite, or marbleand are characterized by the calciphilicspecies listed above. Northern white cedaris often abundant.

RELATED COMMUNITIESMesic Maple-Ash-Hickory-Oak

Forest: This community has a canopyclosure over 60 percent and has well-developed, stable soils. Steeper, richerexamples of this community may be verysimilar to Transition Hardwood TalusWoodland, and the two may occur side byside.

Rich Northern Hardwood Forest:Where the canopy is dense and soils aremore stable, Rich Northern HardwoodForests may be found adjacent to TransitionHardwood Talus Woodlands. The twocommunities share several uncommon orrare species.

Bulblet fern – Cystopteris bulbifera




TREESAbundant SpeciesButternut – Juglans cinereaBasswood – Tilia americanaNorthern white cedar – Thuja occidentalisWhite ash – Fraxinus americanaSugar maple – Acer saccharumRed oak – Quercus rubraShagbark hickory – Carya ovataBitternut hickory – Carya cordiformisOccasional to Locally Abundant SpeciesHophornbeam – Ostrya virginianaEastern hemlock – Tsuga canadensisHackberry – Celtis occidentalisSweet birch – Betula lenta

SHRUBSAbundant SpeciesMountain maple – Acer spicatumOccasional to Locally Abundant SpeciesBladdernut – Staphylea trifoliaCanada yew – Taxus canadensis

HERBSAbundant SpeciesHerb Robert – Geranium robertianumBulblet fern – Cystopteris bulbiferaOccasional to Locally Abundant SpeciesClimbing fumitory – Adlumia fungosaWild ginger – Asarum canadenseRusty woodsia – Woodsia ilvensisPellitory – Parietaria pensylvanciaClearweed – Pilea pumilaWhite snakeroot – Eupatorium rugosumPurple clematis – Clematis occidentalis

RARE AND UNCOMMON PLANTSWhite-flowered leafcup – Polymnia canadensisUpland boneset – Eupatorium sessilifoliumGoldie’s wood fern – Dryopteris goldianaBlack maple – Acer nigrumClimbing fumitory – Adlumia fungosaHairy wild rye – Elymus villosusNorthern stickseed – Hackelia deflexa var.americana

Back’s sedge – Carex backiiSprout-bearing muhlenbergia – Muhlenbergiasobolifera

Slender-flowered muhlenbergia – Muhlenbergiatenuiflora


Northern Hardwood TalusWoodland: This is a similar community,but lacks the warm climate species likeshagbark hickory, sweet birch, andbitternut hickory.


MANAGEMENT CONSIDERATIONSThis is an uncommon community in

Vermont. Where logging is possible, itshould be done with care to avoid erosion,and should be restricted to single treeharvest conducted in winter.

PLACES TO VISITShaw Mountain Natural Area, Benson,

The Nature ConservancyMount Independence, Orwell, Vermont

Division of Historic PreservationSnake Mountain, Addison, Vermont

Department of Fish and Wildlife

Bulblet fern detail

Oak-Pine-Northern Hardwood Forest Formation

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Transcript of Oak-Pine-Northern Hardwood Forest Formation