State 1
Reference State / Minimally Managed

Figure 12. Mature mesic clayplain forest showcasing diverse species of overstory hardwoods and a diverse understory of forbs. This picture was part of the 2015 NatureServe Ecological Site Inventory project.

This state represents the reference mesic clayplain forest. The tree canopy is generally closed to partially open. Shrub and herb layers are of variable cover. These were once expansive forests within the Champlain Valley prior to European settlement and have since been subjected to intensive land use conversion and disturbances.

Community 1.1
Late Successional Mesic Clayplain Forest

Figure 13. Mature Mesic Clayplain Forest. Image taken during 2015 NatureServe agreement for Ecological Site Inventory of the Champlain Valley.

This condition represents the dominant historical condition of mesic clayplain forests. These are typically uneven age late successional forests (Thompson, Sorenson, and Zaino, 2019). Dominant drivers consist of localized disturbances from wind events and ice storms, creating tip ups that provide microhabitats for understory species and tree regeneration. Fire was thought to be the preeminent driver of oak regeneration (whether intentionally lit by local tribes or entering the community from pyrogenic uplands), preventing shade tolerant species from being dominant (Murray and D’Amato, 2019). Other limiting factors to oak regeneration are believed to be wind disturbances (not creating canopy gaps large enough for oak regeneration to successfully recruit into the overstory), deer browse, and past land use (fragmentation of habitat prevents seed dispersal, agricultural conversion, etc.). These will typically occur on more sloping land were clearing for past agriculture may not have occurred. This community correlates with NatureServes 'Quercus alba - Acer rubrum - Carya ovata / Viburnum acerifolium / Waldsteinia fragarioides Clayplain Forest' Association (CEGL006122).

Forest overstory. The closed canopy is Green ash, and Swamp wite oak admixed with slippery elm and red maple. Occasional trees include white pine and eastern hemlock. Northern white cedar is sometimes present.

Forest understory. The shrub layer is typically well developed consisting of Viburnum acerifolium (Maple-leaf viburnum), Rosa carolina (Carolina rose), Hamamelis virginiana (witch hazel), Rubus pubescens (dwarf raspberry), R. hispidus (swamp dewberry) and / or Vaccinium angustifolium (low sweet blueberry). The herb layer can be dense and very diverse, consisting of Waldsteinia fragariodes (barren strawberry), Moehringia lateriflora (grove sandwort), Impatiens capensis (jewelweed), Geranium maculatum (wild geranium), Uvularia sessilifolia (sessile-leaf bellwort), and Circaea lutetiana (large enchanter’s nightshade). Graminoids may be sparse to locally abundant, typically occurring in canopy openings where light hits the forest floor. These may include Carex gracillima (graceful sedge), C. laxiculmis (loose sedge), C. rosea (rosy sedge), and C. pensylvanica (woodland sedge).

Community 1.2
Graminoid / Low Shrublands - Absent to Very Sparse Overstory - (Temporary Dominance)

Figure 14. Canopy gap opening representing a graminoid dominant phase consisting primarily of Carex and other forbs in lesser amounts. Vegetation subplot note within NASIS Veg Plot ID 2024VT007001.

This condition represents graminoid dominant and shrublands of temporary dominance following localized disturbances. This can be the result of large-scale disturbances such as clear cuts or naturalized mortality from wind events. Increased light availability allows for the dominance of shrubs and annual forbs while available tree saplings begin to grow into the overstory.

Forest overstory. The overstory will often be absent of live trees or very sparse, allowing for high amounts of light to reach the forest floor and the temporary dominance of understory species to flourish before saplings become dominant and grow greater than 15 feet in height.

Forest understory. These may consist of both native and introduced shrub species such as Vibrunum dentatum (southern arrowwood), Rubus pubescens (dwarf raspberry), R. hispidus (swamp dewberry), Rhamnus cathartica (common buckthorn), Fragaria virginiana (common strawberry), Lonicera morrowii (Morrow’s honeysuckle), Acer platanoides (Norway maple), and Rosa multiflora (multiflora rose).

Community 1.3
Mixed Pine - Early Successional Mesic Clayplain Forest

Figure 15. White pine- early successional species dominant forest on gentle slopes. The understory consists of primarily herbaceous litter and sparse forbs. Mid-successional hardwood trees are beginning to emerge. NASIS Veg Plot ID 2024VT021002,

Figure 16. White pine (Pinus strobus) dominated forest on gentle slopes. These are often a result of post agriculture succession or past harvest. Other early successional species are beginning to emerge. NASIS Veg Plot ID 2024VT001002.

Figure 17. White oak (Quercus alba) seedling present in the understory among a high amounts of pine litter and other forbs. NASIS Veg Plot ID 2024VT001002.

This condition represents the successional condition of a post-harvested or long-term agricultural abandonment reverted to an even-aged early succession forest. In time, pine and other early successional species will begin to thin out and will become replaced with mid- to late-successional species like that of the reference community. Oak regeneration and saplings are often minimal without small scale disturbances.

Forest overstory. Pinus strobus (white pine) is a canopy dominant, often of a single age class, but mixed with various other early to mid-successional species. These may include species such as Fraxinus pennsylvanica (green ash), Populus tremuloides (quaking aspen), Juniperus virginiana (eastern red cedar), Acer rubrum (red maple), Betula papyrifera (paper birch), Quercus macrocarpa (bur oak), and Fraxinus americana (white ash) may become dominant for a period. Shade tolerant mid to late successional species such as Tusga canadensis (eastern hemlock) and Fagus grandifolia (American beech) may be present in some amount in the midstory and understory

Forest understory. The understory is highly variable, but will often consist of a high percentage of leaf litter, predominantly pine needles. Forbs and low shrubs will be present in small amounts and tree regeneration will occur as single scattered individuals.

Community 1.4
Mid-Successional Mesic Clayplain Forest

Figure 18. Mid-successional clayplain forest with early to mid succession hardwood species dominant in the overstory and an understory of herbaceous litter, shrubs and forbs. NASIS Veg Plot ID 2024VT007001

Figure 19. Mid-successional forest with shagbark hickory, green ash, and maples present as moderate sized canopy trees with shrubs and forbs dominant in the understory. NASIS Veg Plot ID 2024VT007001.

Figure 20. Burr oak (Quercus macrocarpa) seedlings present in the understory of a mid-successional clayplain forest. NASIS Veg Plot ID 2024VT007001.

This condition represents a mid-successional mesic clayplain forest, distinguished by the lack of pine and oak dominance in the overstory and minimal oak recruitment in the understory as well as the dominance of aggressive non-native, invasive shrubs. These are often the result of secondary growth stands or stands that have been converted from agriculture. Early successional species have lost their dominance in the overstory and is replaced by a mixed hardwood stand of mid- to late-successional species. This will typically occur in lesser sloped areas that have been cleared in the past for agricultural uses and are currently secondary growth.

Forest overstory. Hardwoods such as Betula lenta (sweet birch), Acer rubrum (red maple), Cayra ovata (shagbark hickory), Ostrya virginiana (eastern hophornbeam), and Fraxinus americana (white ash) are often present in the overstory. Conifers may include Pinus strobus (white pine) and / or Tsuga canadensis (eastern hemlock) in variable amounts. Remnant pine will often be present as a relict emergent canopy but are losing dominance and following tip ups will allow for release of understory saplings. Invasive species such as Acer plantinoides (Norway maple) will often make up variable amounts in the overstory.

Forest understory. Diverse forbs and low shrubs will often be present in the understory. Oak regeneration and saplings are often minimal. Invasive understory shrubs are often present, and will include but are not limited to Lonicera morrowii (Morrow's honeysuckle), Lonicera tatarica (tatarian honeysuckle), Berberis thunbergii (Japanese barberry), Rhamnus cathartica (European buckthorn), and Frangula alnus (alder buckthorn) may be present in the understory.

Pathway 1.1A
Community 1.1 to 1.2

Late Successional Mesic Clayplain Forest

Graminoid / Low Shrublands - Absent to Very Sparse Overstory - (Temporary Dominance)

This transition may occur through large-scale disturbances including but not limited to clearcutting, large-scale wild events (hurricanes, nor'easters, etc.), pest insect outbreaks (emerald ash borer, etc.) or mortality from extreme snow / ice events. Fire in these systems may have been historically utilized by Native Americans. No recent reports of fire in these habitats has been issued.

Pathway 1.1B
Community 1.1 to 1.3

Late Successional Mesic Clayplain Forest

Mixed Pine - Early Successional Mesic Clayplain Forest

This transition may occur through small scale disturbances, often seen but not limited to single tree tip ups and mortality, or selective harvesting.

Pathway 1.2A
Community 1.2 to 1.3

Graminoid / Low Shrublands - Absent to Very Sparse Overstory - (Temporary Dominance)

Mixed Pine - Early Successional Mesic Clayplain Forest

This transition may occur as natural succession over time. As canopy gaps create areas of temporary importance dominated by shrubs and graminoids, assuming a seed source is available, seedlings and sapling will begin to grow. Fast growing shade intolerant species such as white pine are often dominant in the regrowth process.

Pathway 1.3A
Community 1.3 to 1.2

Mixed Pine - Early Successional Mesic Clayplain Forest

Graminoid / Low Shrublands - Absent to Very Sparse Overstory - (Temporary Dominance)

This transition may occur through large- or small-scale disturbances including but not limited to clearcutting, large-scale wild events (hurricanes, nor'easters, etc.), pest insect outbreaks (emerald ash borer, etc.) or mortality from extreme snow / ice events. Fire in these systems may have been historically utilized by Native Americans. No recent reports of fire in these habitats has been issued.

Pathway 1.3B
Community 1.3 to 1.4

Mixed Pine - Early Successional Mesic Clayplain Forest

Mid-Successional Mesic Clayplain Forest

This transition may occur as natural succession over time. White pine and other early successional species will either self-thin or can be thinned manually as time passes, opening the canopy for mid-successional hardwood species to begin to grow.

Pathway 1.4A
Community 1.4 to 1.1

Mid-Successional Mesic Clayplain Forest

Late Successional Mesic Clayplain Forest

This transition may occur as natural succession and oak recruitment in the understory create a forest resembling the reference condition of a late succession mesic clayplain forest. Pine will have lost its dominance in the canopy and be replaced by oak and other mixed hardwood dominance. Many of these forests will require some sort of management to address invasive or non-native plant species and can be removed via chemical, biological, or mechanical means.

Pathway 1.4B
Community 1.4 to 1.2

Mid-Successional Mesic Clayplain Forest

Graminoid / Low Shrublands - Absent to Very Sparse Overstory - (Temporary Dominance)

This transition may occur through large- or small-scale disturbances including but not limited to clearcutting, large-scale wild events (hurricanes, nor'easters, etc.), pest insect outbreaks (emerald ash borer, etc.) or mortality from extreme snow / ice events. Fire in these systems may have been historically utilized by Native Americans. No recent reports of fire in these habitats has been issued.

State 2
Agricultural Row Crops

Figure 21. Corn field in the early growing season (May) 2024 on a conventionally tilled site. NASIS Veg Plot ID 2024VT001001.

This state represents a once forested area now cleared for cropland. This will typically only occur on gentler slopes (less than15 percent) due to potential for water erosion. Corn is the dominant agricultural row crop on this site.

Community 2.1
Conventional Tilled Row Crops

Figure 22. Conventional tilled corn field on gentle slopes of the Champlain Valley. NASIS Veg Plot ID 2024VT001001.

Figure 23. Aerial photo showing spacing between rows, expressing bare soil and cracking due to the high shrink-swell potential of these soils. NASIS Veg Plot ID 2024VT001001.

This phase consists of cleared and cultivated fields for annual or perennial crops that are heavily managed with regular soil disturbances.

Community 2.2
Conservation Till Row and Cover Crops

This phase consists of cleared and cultivated fields for annual or perennial crops that are managed with a conservation focus on tilling practices. These methods include strip till, vertical till, or no till systems. These methods may improve soil ecosystem function over time.

Pathway 2.1A
Community 2.1 to 2.2

This transition can occur through the reduction or elimination of conventional tillage practices and the implementation of conservation practices. Conservation strategies may vary depending on local site conditions and should be addressed with management planners. Through the long term conservation practices, soil physical and chemical properties should improve and pose less of a risk with land management issues.

Pathway 2.2A
Community 2.2 to 2.1

This transition can occur through the use of intensive, regular mechanical soil disturbances.

State 3
Managed Grassland

Figure 24. First cut hay field in May of 2024 found on a Madalin taxadjunct series in Shelburne, Vermont. NASIS Veg Plot ID 2024VT007002.

This state represents a once forested area now cleared and managed as pasture or hay fields. This will typically only occur on gentler slopes (less than15 percent) due to potential for water erosion. Pasture vegetation can consist of grasses, legumes, other forbs, shrubs or a mixture. Many of these forages are introduced, having originally come from areas in other states or continents. Overgrazed pastures can lead to soil compaction and numerous bare spots, which may then become focal points of accelerated erosion and colonization sites of undesirable plants or weeds.

Community 3.1
Orchardgrass - Smooth Brome - Common Milkweed Early Successional Meadow

Figure 25. Third cut hay field late in the growing season (August) of 2024. NASIS Veg Plot ID 2024VT021001.

Figure 26. Hay field cut exclusion for wildlife habitat showing species seeding and what prior to haying would look like. Included as a site note adjacent to NASIS Veg Plot ID 2024VT021001.

This community phase represents commonly planted forage species on pastureland and hay land. The suite of plants established on any given site may vary considerably depending upon purpose, management goals, and usage (e.g., horse vs. cattle). Most systems include a mixture of non-native cool-season grasses and legumes that provide forage throughout the growing season. Several additional plants and/or species combinations maybe present depending on the objectives and management approaches of the land manager/owner. This may also be the result of bare soil after cessation of agriculture, and will be short-lived without annual mowing, but can persist indefinitely when actively managed.

Resilience management. Mechanical mowing, at least annually but ranging up to four times during the growing season, helps maintain these areas as dominant grasslands.

Forest overstory. Trees and shrubs are generally absent from these communities but may occur as scattered mature individuals as shade structures for grazing animals.

Forest understory. Common species may include cool season grasses such as Dactylis glomerata (orchardgrass), Bromus inermis (smooth brome), Phleum pratense (timothy), Anthoxanthum odoratum (sweet vernal grass), Poa pratensis (Kentucky bluegrass), Agrostis spp. (bentgrass), Festuca rubra / ovina (red / hard fescue), Lolium perenne (perennial rye), and x Festulolium. Legumes may include Medicago sativa (alfalfa), Trifolium pratense (red clover), and Astragalus spp. (milkvetch). Forbs may be less abundant and can include Galium spp. (bedstraw), Fragaria virginiana (Virginia strawberry), Heracleum spp. (cowparsnip), Rhinanthus spp. (yellow rattle), Solidago spp. (goldenrods), Ranunculus spp. (buttercups), & Hieracium spp. (hawkweed).

Community 3.2
Autumn Olive - Gray Dogwood - Multiflora Rose Ruderal Shrubland

This vegetation comprises shrubby old fields dominated by thickets. Variable amounts of invasive plants are present. Small trees are often present but often form less than 25% cover and consist of early successional species. The herbaceous layer is variable depending on the density of shrub cover. Typical species are those associated with old fields, grasslands, and agricultural sites. Vines can be absent or dominant, sometimes covering the tall and short shrubs. This phase is characterized by an abundance of fleshy fruited shrubs, both native and non-native, that become established by bird and small mammal dispersal. Many of the successional meadow species remain in openings, usually forming a patchy mosaic (NatureServe 2015). This correlates with NatureServes 'Elaeagnus umbellata - Cornus racemosa - Rosa multiflora - Juniperus virginiana Ruderal Shrubland' Association (CEGL006451).

Pathway 3.1A
Community 3.1 to 3.2

This may occur when grassland management operations are reduced or eliminated, allowing for succession to predominately invasive and incursive shrubs.

Pathway 3.2A
Community 3.2 to 3.1

This may occur through the removal of undesirable species in a managed grassland and return to specific management practices for pasture or hay production.

State 4
Potential Restoration State

This state represents an altered state that is undergoing restoration to reflect the mesic clayplain forest in composition and structure but also reflects the past land use. This may include a variety of phases that may or may not be successful.

Community 4.1
Even-Age Planted Saplings

This phase represents the beginning of restoration, in which saplings of the appropriate species are planted at the desired density. These may need to be protected from the browse of animals. The ground cover may be bare ground or undesirable pasture grasses and forbs.

Community 4.2
Even-Age Sapling Forest / Shrubland

This phase represents the even aged stand of saplings that have become established and begin growth at the desired density. The groundcover may be a mix of native and non-native species as well as variable amounts of bare ground.

Community 4.3
Uneven-Aged Sapling Forest / Shrubland

This phase represents a restoration attempt in which the trees may become different age classes, whether intentionally or not. Some saplings will become established and begin growth at undesired density, until natural seeding or replanting occurs. The groundcover may be a mix of native and non-native species as well as variable amounts of bare ground.

Pathway 4.1A
Community 4.1 to 4.2

This may occur when planted species become established at a restoration site and begin to grow under passive and active management.

Pathway 4.1B
Community 4.1 to 4.3

This may occur through single or group species die off and replanted or regrowth of species occurs. Species die off may occur through many reasons, including but not limited to herbivory, fungal disease, insect outbreaks, lack of nutrients, unsuited planting, etc.

Pathway 4.2A
Community 4.2 to 4.3

This may occur through single or group species die off and replanted or regrowth of species occurs. Species die off may occur through many reasons, including but not limited to herbivory, fungal disease, insect outbreaks, lack of nutrients, unsuited planting, etc.

Transition T1A
State 1 to 2

Reference State / Minimally Managed

Agricultural Row Crops

Converted forested communities have often undergone the clearing of native vegetation and site preparation before conversion to agricultural fields is complete. Due to the complex microtopography of the native site, land smoothing and / or leveling may be required, as well as undergoing practices such as tilling for the field to be ready to plant. Planting of desired crops can be done by hand or machine at desired spacing and intervals.

Transition T1B
State 1 to 3

Reference State / Minimally Managed

Managed Grassland

Converted forested communities have often undergone the clearing of native vegetation and site preparation before conversion to a managed grassland state is complete. Due to the complex microtopography of the native site, land smoothing and / or leveling may be required. Planting of desired mixtures of grasses and / or legumes can be done by hand or machine at desired densities.

Transition T2A
State 2 to 3

Agricultural Row Crops

Managed Grassland

Cropland can be converted to managed grasslands following the removal of the crop and the planting of desired mixtures of grasses and / or legumes at the desired density. Short term abandonment of crop fields may also give rise to ruderal shrublands and undesirable grasses and forbs that, if managed correctly, can be converted into a persistently managed grassland.

Restoration pathway R2A
State 2 to 4

Conversion from an agricultural state to a restored function state may require the removal of the crop and the reintroduction of tree saplings and other native species to the area. Measures may need to be taken to prevent excessive soil erosion and failure of establishment due to browse.

Transition T3B
State 3 to 1

Managed Grassland

Reference State / Minimally Managed

Long-term abandonment of converted land may result in fallow fields that will allow for the growth and establishment of native and non-native species that over time can reflect an early- to mid-successional forest of the reference state. The presence of non-native species will often diminish the ecological value of the restored forest, but through proper management and care may reflect the reference condition over time.

Transition T3A
State 3 to 2

Managed Grassland

Agricultural Row Crops

Managed grassland can be converted to agricultural fields following the removal of the grasses / legumes (typically achieved by tilling) and planting the desired crop at the desired spacing and intervals.

Restoration pathway R3A
State 3 to 4

Conversion from a managed grassland state to a restored function state may require the cessation of management and the reintroduction of tree saplings and other native species to the area. Measures may need to be taken to prevent excessive soil erosion and failure of establishment due to browse. Passive restoration management may result in a condition similar to an old-field white pine forest, whereas active restoration management may result in more diverse species composition.

Transition T4A
State 4 to 1

Following the success of tree sapling establishment in restoration areas, natural seeding can occur and result in regrowth of forest species to the proper age and site classes.