Autumn Leaves 

(Tree list at the bottom of post.)

Greenfield Lake at Peak Foliage 

Autumn brings many changes to the natural landscape and as in previous articles, animals change their behaviors to prepare for winter.  Some species of birds migrate out of the Carolinas after breeding, while others stop by to refuel or rest. Squirrels, and certain woodland birds stockpile food to survive the winter. You may also see other behaviors such as mockingbirds and thrashers guarding berry bushes, katydids and crickets singing at a slower pace as the temperatures cool, and an abundance of spiders (as evidence by their webs on misty mornings). Plants also undergo transformations during autumn. Autumn wildflowers like goldenrod, Swamp Sunflower, ironweed, dogfennel, and asters are blooming in meadows, while other plants go to seed or produce fruits and berries for migrating birds.  Deciduous trees, shrubs, and vines shed most or all of their leaves during the autumn as they prepare for winter. We see this as autumn or fall colors. 

Changing Leaves

Peak foliage time. Map courtesy of Wikimedia Foundation. 

Many species of trees will shed their leaves during the autumn. Some trees such as conifers and broad-leaved evergreens only replace some of their leaves or needles. Others like deciduous trees will lose all of their leaves. Plants do this to conserve energy during the winter, and to minimize damage caused by frost. In the Carolinas, autumn foliage transitions begin from the end of September until November with some trees like Turkey Oak being among the last trees to change. The Highlands of Appalachia are the first regions to undergo transitions, followed by the valley regions and then the Piedmont Region of Carolina. On the Coastal Plain, the autumn foliage not as  extensive as many of the tree species are evergreen or semi-evergreen and do not change colors. The same is the case for the Balsam Forests of the Blue Ridge above 1520m (5000ft) as conifers are the dominant species. 

In the Cape Fear Region, autumn foliage sets in in late September but does not peak until the third week of November. Some trees such as Turkey Oaks will not change until December, making our leaf peeping season extend over four months. However, compared to the Northeastern United States, Southern Canada and the Appalachian Corridor, our autumn foliage is not that impressive. Many trees in the Wilmington area are evergreens and the warmer temperatures may result in some native trees, and many nonnative trees that came from other regions retaining their leaves all year long. We still have some nice spots. Unlike areas directly along the seacoast or Sandhills Regions (just inland of us), we have enough deciduous trees to make some areas look good by November. 

Why do Leaves Change?

Bald Cypress and Tupleos near NHC Nature Trail near College Road

Autumn color by a change in a leaf's pigment. Leaves are normally green because the pigment or chlorophyll within a plant's chloroplasts masks the the other pigments. This is why hardwood forests are bright green or yellowish in the spring, and turn to a darker color by midsummer. When temperatures cool and daylight becomes limited, the vanes that feed fluids to the leaf are closed off, reducing water and mineral intake. Chlorophylls will break down as the leaves begin to "shut down" revealing other pigments that are present in the leaf. These pigments combine  to create a red, orange, yellow, magenta, or even pinkish coloration while the vanes remain green. This is a simplified reason for why the leaves of deciduous trees and shrubs turn colors. For more information you can start at this Wikipedia Article about Autumn Colors. 

What Trees Change Colors 

Sweet Gums, and Tupleos in autumn

All trees, shrubs, and vines will shed their leaves at some point in a growing season. Conifers and many evergreen hardwood trees may lose their leaves throughout the year or during a season. The leaves and needles of these trees have waxy coats that protect them from frost, allowing them to survive freezing temperatures. In general, deciduous trees and a very small number of conifers will undergo color changes during the autumn because of the pigments explained above. Semi-evergreen trees will also change colors when some of the leaves are shedded away. In addition to trees and shrubs, many species of vines, as well as some herbaceous plants will undergo color changes  as well. Grasses in a grassland, meadow, or marsh change colors during the late summer or autumn when they are producing seeds, while many spring herbs like Trillium or Bluebells will yellow once their finish flowering.

Where to Look

Chinese Gingko at peak color

In the Carolinas, the best colors are found in forests or woodlands with maples, deciduous oaks, hickories, sweetgums, dogwoods, and ash trees. Most of the hardwood forests in Appalachia and the High Piedmont will transition into a fiery blaze of red, orange, yellows, and greens from October to early November. In the Coastal Plain, the colors are limited to deciduous or mixed forest habitats such as Riverbottom Forests, swamps, or in woodlands dominated by hardwoods. Towns, cities, and  villages often use hardwoods as street trees or for plantings in parks.  People plant deciduous trees in their gardens or property for shade during the summer, while allowing more light during the winter months. For this reason, towns and residential areas may be local gems for leaf peeping if we are unable to head to the mountains or further north.

In Southeastern North Carolina, autumn colors are the most extensive in and around riverine or wetland forests, and in patches of Eastern Deciduous Forests away from the coast. While pines, and evergreen oaks dominate our canopy, there are enough deciduous hardwoods to create some color if you know where to look. 

Baldcypress Swamps: Baldcypress and its relative the Pond Cypress are some of the few conifers that actually lose all of their needles (with Tamarack Pine being another example). From late September to November, cypress trees gradually from their deep green coloration to a dark orange and eventually a brownish color before the needles are completely gone by November. This gives us three months of foliage that changes with each each week. On top of the Baldcypress trees, these forests have Red Maples, Sweetgums, tupelos, dogwoods, sycamores, alder, willow, ash, and poplar that become a firestorm of red, purple, yellow, and gold. Lastly, there are vines like Virginia Creeper, Fox Grape, Poison Ivy, American Wisteria (and the Invasive Japanese species) and Climbing Hydrangeas that change colors as well. With all of these elements in place, a swamp or bottomland forest can be as breathtaking as any forest or woodland in Appalachia. For the Carolina Coast, this is as good as it gets unless you visit a garden or park that is landscaped with only deciduous trees. 

Greenfield Lake Park arguably has some of the best autumn foliage in Wilmington and any visit from the last week of September to the end of October will yield nice photo opportunities, "Appalachian-like color palates" and plenty of migratory birds and butterflies to go with it. The NHC Nature Trail across from Longleaf  Park (formerly Hugh McRae Park) is another breathtaking spot. There is a wooded bridge that overlooks a marsh and  a stand of Bald or Pond Cypress mixed with hardwoods. There are other places across New Hanover, Pender, Brunswick, and Hoary County with this type of forest. 

Mixed Forests: Mixed forests are the next best option for autumn foliage in our area. These woodlands can be found anywhere and are often the result of pine savannas or native grasslands  reverting to hardwoods due to fire suppression. Natural mixed forests can also be found in inland regions of the Cape Fear. These forests contain Red, Silver, or Southern Sugar Maples, Sweetgums, ash, birch, and as many as a dozen varieties of oaks or hickories. There are also pines, Red Cedars,  junipers, and evergreen hardwoods  like Live Oak, Laurel Oak, and American Holly. By early November, these woodland areas transition into a sea of yellow, orange, and red with everything in between. The pines, cedars, and evergreen oaks create a nice backdrop. Examples of areas with mixed or pure deciduous forests include Ev Henwood Preserve in Brunswick County, parks such as Maides Park, Castle Hayne Park, or sections of the Cross City Trail in Wilmington. 

Sandhill Forests: When we think autumn has past and the trees at the other forests types above finish, there is an encore performance. In dry pine-oak barrens in Eastern North and South Carolina, trees such as Turkey Oak, Black Oak, Pin Oak, and Post Oak will not change colors until December. During the final weeks of Autumn, the understory and subcanopy sections of these fire-dominated forests becomes into a breathtaking mix of reddish brown, orange, and purple. The oaks will hold on to their leaves well into winter with some color remaining as late as January. Halyburton Park in Wilmington is by-far the best example of this phenomenon with the entire 1.2 mile loop covered in pine-oak barrens. Carolina Beach State Park, and some rural highways in Brunswick, Hoary, and Columbus County also cut through pine barrens and sandhill forests. 

Wilmington: The City of Wilmington is also a good place to  get a taste of autumn foliage. Most of the older neighborhoods and parks near the city center feature streets lined with oaks and hickories, copses and groves of hardwoods, and remnant forest patches. To add to the color palate, many private gardens as well as public areas have nonnative plants that bring good foliage with Japanese Maple, Crepe Myrtle, Kousa Dogwood, and even northern hardwoods like Sugar Maple, Aspen, and Yellow Birch being planted in some gardens. Older communities also have Black Walnuts, Pecan Hickory, and Butternuts leftover from old farms, as well as persimmons, pears, and figs. The Black Walnut and Pecan Hickory turns golden yellow in November, making these one of the most gorgeous trees in our flora (aside from the Chinese Ginkgo Tree planted in some parks). Even baddies like Chinese Tallow Tree "Popcorn Tree", Princess Tree, and Japanese (or Chinese) Wisteria can produce wonderful colors in a garden or park setting. The best places to leaf-peep in Wilmington are along older neighborhoods near downtown including along Princess Place Drive, Market Street, and the Historic District. Some of the parks mentioned above also fall into this category. 

Trees and Shrubs by Color 

Turkey Oak 

Trees and Shrubs

• Red Maple: Red to magenta 
• Silver Maple and Sugar Maple: Bright yellow or gold 
• Sweetgum: Golden yellow to scarlet (flame-colored)
• Bald Cypress: Starts amber and transitions to an orange color before browning 
• Dogwoods: Pastel orange, purple, red, and yellow 
• Ashes: Bright yellow or gold 
• Hickories: Usually bright yellow, gold, or "slightly orange" 
• American Beech: Gold before turning brown 
• American Sycamore: Yellowish to brown 
• White Oak, Swamp White Oak: Reddish
• Red, Southern Red, Post, Black, Turkey Oaks:  Reddish Brown or orange
• Willow, and Water Oak: Yellow
• Birches, Ironwoods, and Alders: Yellow to gold
• Willow: Yellow or gold
• Elms: Yellow
• Tulip Poplar: Yellow 
• Basswood: Yellow or orange 
• Persimmon: Yellow
• Redbud Yellow
• Tupleos: Yellow or reddish 
• Cherries: Red to orange
• Sumacs: Red or orange 
• Sassafras: Yellow, orange, or reddish 
• American Plum, Chickasaw Plum, Hawthorns, Crabapple: Yellow or gold 
• Hackberry: Yellow
• Crepe Myrtle: Yellow-orange with some red 
• Japanese Maple: Purple, magenta, or scarlet red 
• Tallow Tree: Bright red to scarlet 
• Hydrangeas: Yellow to reddish depending on species 
• Swamp Azalea: Yellow or gold  
• Blueberries: Reddish orange 
• Swamp Rose, Carolina Rose: Yellowish 

Major Vines 

• Virginia Creeper: Red, orange, or magenta 
• Peppervine:  Yellow to gold 
• Wisteria (all species): Golden yellow 
• Climbing Hydrangea: Yellow  
• Trumpet Creeper: Yellow 
• Poison Ivy/Poison Oak: Yellow to reddish 
• Mourning Glory: Yellowish brown  
• Coral Honeysuckle: Yellow
• Kudzu: Yellowish brown 

Birds and Cyclones

Birds and Cyclones

Tropical Storm Isaias on August 3rd, 2020. Source: NOAA 

Tropical Cyclones or in our region Hurricanes are complex weather systems that often bring strong winds, flooding rains, and storm surges to coastal areas. The coastal regions of the Carolinas experiences tropical systems from midsummer to mid-autumn with peak months being August through early October. Wilmington has had its share of cyclones with Hurricanes Hazel (1954), Donna (1960), Fran (1996), Floyd (1999), Matthew (2016), and Florence (2018) bringing major impacts to our area. These storms often come with destruction, loss of life, as well as extensive disruption to natural ecosystems already stressed by human activities. However, like all forces of nature, tropical cyclones are a part of natural processes and may provide beneficial rainfall, wash out stagnate areas, and reshape our coastline. Regardless of their benefits, tropical systems are just as dangerous to birds and wildlife as they are to us. A major storm can permanently reshape ecosystems, and could lead to extinctions in places where rare or endangered animals or plants are confined to a small area such as an Island. Birds are highly mobile and many of our species can survive violent storms or move out of the way in time. 

Birds and Hurricanes

Parula (left) and Redstart (top right) in hedge, 1 month after Hurricane Florence 

Like us, birds are vulnerable to the effects of severe weather, and a large-scale event can cause widespread destruction across a large area. As stated above, birds have the benefit of flight and many of our species can fly inland or to sheltered areas. Additionally, hurricanes generally peak in the late summer or early autumn when nearly all nesting activity is finished and birds are in migration. However in exceptional cases where storms occur in May, June or July, the impacts to nesting cycles can be significant, especially for coastal species. Birds are capable of sensing changes in weather or air pressure follow their instincts to get to cover or relocate. Some birds that end up being caught in cyclones may be carried hundreds of miles out of their normal range. In most situations, birds will emerge from storms largely unharmed, although even weak cyclones (like tropical storms) can significantly alter habitats. This is both beneficial and harmful. In the short term, flooding, loss of trees and saltwater intrusion will reduce suitable habitat, wipe out food sources, and kill many animals. As time goes on, ecosystems will recover or transition into new habitats, providing places for other species to population, or by thinning overforested areas to allow for local diversity. In populated areas, storms can potentially destroy fragment ecosystems or generate hazardous waste and pollution from destroyed buildings, overflowing sewer mains, and debris. Rebuilding, recovery, and oftentimes individual actions to minimize risk to life or property can further stress urban ecosystems as trees and wooded areas are cut back to protect homes, or power lines. In the end, natural will always adapt to changes and birds are often the first creatures to return to storm-devastated areas. 

Bird Notes 

• Coastal birds such as terns, skimmers, pelicans, waterfowl, and shorebirds often fly to inland areas to seek protection. In Hurricane Florence, Black Skimmers and other seabirds were found near fields or retention ponds in Wilmington 

• Many songbirds and landbirds seek shelter in undergrowth, trees, or wooded areas and will often remain safe even if trees fall 

• A significant number of birds end up caught in the storm and may be carried long distances. Everything from songbirds to albatrosses may be stuck in the eye of powerful cyclones, resulting in them being found way out of range 

• I found bird tables and feeders to be particularly busy after storms as insects, natural seeds or fruits, and other food sources are reduced. Hurricane Florence stripped leaves and branches from trees, resulting in birds finding alternate sources of food 

• Most nesting species are finished by August although rare early season storms can affect shore nesting birds. 

Impacts 

Flooded woodland trail in NHC after Hurricane Florence 

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Tropical cyclones can cause significant changes to regional ecosystems across a large area. In most cases, forests, marshes, and shorelines will withstand storms and recover within a season or two. However, violent storms can wipe out entire swaths of forests, eliminate shorelines or barrier islands, and in the case of threatened island ecosystems, cause total destruction. Hurricane Florence in September 2018 was Wilmington's most devastating storm in recent history and caused the destruction of property, infrastructure, and even isolated the city for several days. In addition to human impacts, the cyclone uprooted, or snapped thousands of trees, cleared coastal and interior forests, and brought saltwater up the Cape Fear River. Nearly two years later, many natural have recovered although the loss of canopy has created different ecosystems.

There are many benefits of widespread weather events. One example of this is the felling of hardwood trees, pines, and willows at Greenfield Lake. Tree losses created new meadows and sawgrass/cattail marshes that allowed Red Winged Blackbirds, Common Yellowthroats, and Indigo Buntings to populate many areas of the park. Snapped or dead trees that were not removed by the city gave Pileated, Red Bellied, and Downy Woodpeckers new places to make cavities and expanded Red Headed Woodpecker habitats.  In other areas, regenerating woodlands and meadows are important for declining species such as Northern Bobwhite, Eastern Towhees, Field Sparrows, and Meadowlarks which need open or brushy habitat to breed. In cases of violent hurricanes that destroy most of the trees in an area, the impacts to forest birds can be extensive and long lasting. Hurricane Hugo destroyed many old growth trees near Charleston SC which will take hundreds of years to recover. Hurricane Dorian in 2019 wiped out most of the Bahaman Pinelands and could result in the extinction of several species including the Bahama Nuthatch. 

On the coast, hurricanes can create new inlets, spits, and islands for shorebirds and seabirds. This may have contributed to increased beach area for Least and Common Terns on Wrightsville Beach in 2019. Storms also erase coastal islands and will destroy any active bird or turtle nests on the beach or nearby grasslands. 

Storms of any magnitude will disrupt migration patterns and it is not uncommon for southbound songbirds or seabirds to be pushed northward by storms. Many birds will perish in storms although the losses are not usually significant enough to affect established most bird species. More significantly, passing cyclones will bring many unusual species to areas. Birds from as far as the Caribbean may end up in North Carolina after storms. In the days or weeks following a storm, keep an eye out for unusual songbirds, seabirds, or waterbirds. Less commonly, tropical cyclones may relocate bird populations northward resulting in expansion in range or newly introduced species. 

Recovery and Conservation 

Coastal Restoration project at Brunswick Town, UNCW field trip Nov 2019

It often takes two to five years for the full impact of any major weather event or a change in climate to be fully realized. For example, a dry summer  or cold winter may not impact this year's acorn or insect populations but may result in a food crash 2-3 years later. More research is needed to determine the overall impact that cyclones have on birds in our area and  across the world. Radar tracking programs, citizen science (like birding groups or eBird data), ecological surveys, and climate research are all important tools that can determine the impacts on birds and other wildlife. The data from research will help help to restore hurricane affected habitats, expand breeding populations of rare or endangered species, as well as find new ways to protect both human interests and the environment as a whole.