Mesic Maple-Ash-Hickory-Oak Forest

Ecology and Physical Setting

The Central Hardwood Forests of the southern Appalachians are known for their tall oaks and hickories, and their stunning displays of spring wildflowers. Hints of this impressive forest reach into the warmer regions of Vermont, where we call it Mesic Maple-Ash-Hickory-Oak Forest. These forests are found on mesic sites and see higher-than-average temperatures and lower-than-average rainfall. They have soils that are typically drier than those in the cooler parts of the state. Parent materials are glacial tills. Bedrock can be close to the surface locally, but shallow bedrock usually creates conditions that favor more drought-tolerant communities.

Mesic Maple-Ash-Hickory-Oak Forests are often found on lower slopes, benches, and coves, where colluvial processes result in the accumulation of soil and nutrients. In many settings, these forests are found on south and west-facing slopes, while cooler north and east-facing slopes harbor northern hardwood communities. The combination of the warm, dry climate and deep, fertile soils results in a distinctive mix of oaks and hickories along with northern hardwoods like sugar maple, white ash and basswood. 

Vegetation

Mesic Maple-Ash-Hickory-Oak Forests are diverse. The canopy tends to be a mix of northern hardwoods such as sugar maple, white ash, and basswood, with central hardwoods such as shagbark hickory, bitternut hickory, pignut hickory, white oak, and red oak. Enriched growing conditions in coves and on lower slopes can produce impressively large trees even in relatively young examples of this community. White pine and hemlock are occasionally found in this community but are never abundant. The shrub layer in these forests is sparse to well-developed, depending on the light available. Herb cover also varies, and usually includes species—such as blue-stemmed goldenrod, white snakeroot, and sharp-lobed hepatica—that are indicative of moderate enrichment. Spring wildflower displays can rival those of Rich Northern Hardwood Forests and Dry Oak-Maple Limestone Forests.

The variation in this community is analogous to the variation in Northern Hardwood Forests. Moister sites in coves and hollows will have higher productivity and greater abundances of sugar maple, white ash, white oak, shagbark hickory, bitternut hickory, and basswood, along with a diverse suite of rich-site herbs. Drier and less nutrient-rich settings will have a greater abundance of species such as red maple, beech, black birch, and red oak, and may have depauperate shrub and herb layers.

These forests can provide habitat for species that are common to our south but reach their northern range limits in southern Vermont. Examples include flowering dogwood and round-leaved tick-trefoil. Tulip tree, the classic species of the central hardwoods, grows in this community in extreme southwestern Vermont.

Wildlife Habitat

Wildlife habitat is directly related to the structural complexity of the forest. Mesic Maple-Ash-Hickory-Oak Forests that have structural complexity—in other words, those that have trees of all ages and sizes, numerous large snags, and large fallen trees and their root tip-ups—have conditions that support many wildlife species. In contrast, even-aged forests where all the trees are the same size, with little disturbance that results in dead and downed trees, typically support fewer wildlife species. The mast-producing trees in this community are an important food source for many birds and mammals. Turkeys and gray squirrels are two readily-observed species that rely heavily on mast, but others include deer mouse, white-footed mouse, woodland jumping mouse, and chipmunk. Shagbark hickory is an important tree for Indiana bat and northern long-eared bat. Both bats will roost behind the large flakes of bark.

Mesic Maple-Ash-Hickory-Oak Forests are abundant on the lower slopes in Vermont’s warmer regions. This, combined with the high diversity of tree and shrub species, make it an important habitat for several species of breeding birds, including wood thrush, eastern wood pewee, yellow-throated vireo, ovenbird, scarlet tanager, cerulean warbler, and northern saw-whet owl. This is one of the warm-climate forests into which red-bellied woodpeckers have expanded their range in recent years.

Two uncommon butterflies, hickory hairstreak and West Virginia white, are found in Mesic Maple-Ash-Hickory-Oak Forest, where they are dependent on hickories and toothwort, respectively.

Successional Trends 

White pine, paper birch, black birch, and bigtooth aspen are among the early-successional trees that can dominate these forests following disturbance. Because of their landscape position and relatively moist soils, these forests are not prone to fire. Regeneration of tree species likely occurs best in mature forests where windthrow creates tip-ups and exposed mineral soil in canopy gaps. 

Related Communities

• Dry Oak-Maple Limestone Forest: Shallow calcareous bedrock results in drier and more nutrient-rich conditions than the typical Mesic Maple-Ash-Hickory-Oak Forest. The bedrock is reflected in understory herbs such as bulblet fern, maidenhair fern, wild ginger, large-flowered trillium, and Dutchman’s breeches.
  
   
• Dry Oak-Hickory-Hophornbeam Forest can share many species with Mesic Maple-Ash-Hickory-Oak Forest, but it is found on dry, shallow-to-bedrock ridges and convex slopes with droughty growing conditions. Trees are typically shorter, and the herb layer is characterized by a dense lawn of woodland sedge.
  
   
• Dry Hemlock-Oak Forest is characterized by an abundance of eastern hemlock and is generally found on shallow, acidic bedrock. 
  
   
• Red Oak-Northern Hardwood Forest is generally northern in character. It lacks the white oak and hickory species found in Mesic Maple-Ash-Hickory-Oak Forest.

Conservation Status and Management Considerations

Mesic Maple-Ash-Hickory-Oak Forest is an uncommon natural community type in Vermont. A number of small examples are on conserved lands, but few are mature. Larger examples should be conserved and allowed to become old forests with complex structure. Invasive species pose a substantial threat to many of these forests, especially those recovering from past land clearing, and may be challenging to control. Timber management in these forests should avoid altering the downslope movement of soil and nutrients, maintain a mix of oak, hickory and northern hardwood species in the canopy, and prevent the spread of non-native, invasive species. 

Distribution/Abundance

This is an uncommon community in Vermont, restricted to mesic sites in the Champlain Valley, Taconic Mountains, Vermont Valley, and Southern Vermont Piedmont. It has affinities with forest communities that are more common to our south.

Characteristic Plants

Trees

Abundant Species

White oak – Quercus alba

Bitternut hickory – Carya cordiformis 

Sugar maple – Acer saccharum

White ash – Fraxinus americana

Occasional to Locally Abundant Species

Shagbark hickory – Carya ovata

Red oak – Quercus rubra

Basswood – Tilia americana

Red maple – Acer rubrum

Eastern hemlock – Tsuga canadensis

White pine – Pinus strobus

Paper birch – Betula papyrifera

Hophornbeam – Ostrya virginiana

Butternut – Juglans cinerea

Black cherry – Prunus serotina

Shrubs

Maple-leaved viburnum – Viburnum acerifolium

Shadbushes – Amelanchier spp.

Striped maple – Acer pensylvanicum

Witch hazel – Hamamelis virginiana

Beaked hazelnut – Corylus cornuta 

Herbs

Marginal wood fern – Dryopteris marginalis

White snakeroot – Ageratina altissima

Blue-stemmed goldenrod – Solidago caesia

Zigzag goldenrod – Solidago flexicaulis

Sharp-lobed hepatica – Anemone acutiloba

White baneberry – Actaea pachypoda

Christmas fern – Polystichum acrostichoides

Four-leaved milkweed – Asclepias quadrifolia

Common toothwort – Cardamine diphylla

Lance-leaved wild licorice – Galium lanceolatum

Wild licorice – Galium circaezans

Bearded shorthusk – Brachyelytrum aristosum

Minnesota sedge – Carex albursina

Pedunculate sedge – Carex pedunculata

White avens – Geum canadense 

Maidenhair fern – Adiantum pedatum

Black-seeded mountain rice – Patis racemosa

Naked tick-trefoil – Hylodesmum nudiflorum

Showy tick-trefoil – Desmodium canadense

Wild ginger – Asarum canadense

Non-native Invasive Plants

Morrow’s honeysuckle – Lonicera morrowii

Tatarian honeysuckle – Lonicera tatarica

Japanese barberry – Berberis thunbergii

Common buckthorn – Rhamnus cathartica

Glossy buckthorn – Frangula alnus

Rare and Uncommon Plants

Pignut hickory – Carya glabra

Flowering dogwood – Cornus florida

Round-leaved tick-trefoil – Desmodium rotundifolium

Squawroot – Conopholis americana

Handsome sedge – Carex formosa

Broad beech fern – Phegopteris hexagonoptera

Hitchcock’s sedge – Carex hitchcockiana

Spicebush – Lindera benzoin

Perfoliate bellwort – Uvularia perfoliata

Short-styled snakeroot – Sanicula canadensis

Puttyroot – Aplectrum hyemale

Early blue violet – Viola palmata

Kalm’s brome grass – Bromus kalmii

Sweet Joe-pye weed – Eutrochium purpureum var. purpureum

American ginseng – Panax quinquefolius

Associated Animals

Eastern red-backed salamander – Plethodon cinereus 

Eastern newt – Notophthalmus viridescens 

Gray treefrog – Hyla versicolor 

DeKay’s brownsnake – Storeria dekayi

Southern flying squirrel – Glaucomys volans

Gray fox – Urocyon cinereoargenteus 

Eastern chipmunk – Tamias striatus 

Eastern gray squirrel – Sciurus carolinensis

Eastern wood pewee – Contopus virens

Black-billed cuckoo – Coccyzus erythropthalmus 

Wood thrush – Hylocichla mustelina

Yellow-throated vireo – Vireo flavifrons 

Wild turkey – Meleagris gallopavo 

Red-eyed vireo – Vireo olivaceus 

Ovenbird – Seiurus aurocapilla

Scarlet tanager – Piranga olivacea 

Hairy woodpecker – Picoides villosus 

Rose-breasted grosbeak – Pheucticus ludovicianus 

Tufted titmouse – Baeolophus bicolor 

Rare and Uncommon Animals

Jefferson salamander – Ambystoma jeffersonianum 

Blue-spotted salamander – Ambystoma laterale 

Indiana bat – Myotis sodalis

Northern long-eared bat – Myotis septentrionalis 

Red-bellied woodpecker – Melanerpes carolinus 

Northern saw-whet owl – Aegolius acadicus

Cerulean warbler – Setophaga cerulea 

West Virginia white – Pieris virginiensis

Hickory hairstreak – Satyrium caryaevorus 

Places to Visit

Snake Mountain Wildlife Management Area, Addison, Vermont Department of Fish and Wildlife



Wilmarth Woods, Addison, The Nature Conservancy (TNC)



Helen W. Buckner Memorial Preserve at Bald Mountain, West Haven, TNC



Arms Grant Urban Reserve, Burlington, Burlington Parks and Recreation Department