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 

Autumn Stockpiles

 Autumn Stockpiles

Red Headed Woodpecker with acorn, Myrtle Beach Oct 2019.

Autumn is an interesting time to observe birds and wildlife. In many parts of temperate North America and Europe, autumn means that winter is around the corner. During this time, birds and certain insect species migrate, while some animals like bears, marmots, and certain mice prepare to hibernate. Food is often scarce during the winter months, and even in a mild region like Southeastern North Carolina, birds and animals need a consistent source of food when plants go dormant and insects go into hibernation. Some species of bird and mammals will stockpile food for later use. While it is a common belief that animals store up food for the winter, many birds and mammals will stockpile food throughout the year for various reasons. This behaivor is known as hoarding or caching and is a survival technique to ensure food availability during lean times like frigid winters, extended droughts, rainy weather, or another event that causes food scarcity. Squirrels, mice/rats, crows, jays, shrikes, certain woodpeckers, and small woodland birds are examples of animals that routinely hoard food for later use. 

Hoarding 

White Oak acorn collected on walk around Greenfield Lake

Hoarding or caching is the behaivor of storing or hiding food in deliberate spots for later use. It can serve many purposes in the natural world although the most common reason is to ensure that food is available in times of scarcity. Animals also use this technique to hide precious food sources from other members of their species or from other species and possibly as a  means of ripening nuts or berries. Ants, bees, wasps, and other insects may also store food although this behaivor is different from the food hoarding seen with birds or rodents. Hoarding is most common in the autumn and winter although many birds will save up food throughout the year. Chipmunks, rats, and hamsters stockpile large amounts of food in their dens or in sites called larders. Certain birds like Acorn and Red Headed Woodpeckers will also store their food in a handful of places. Most other birds and mammals store individual items in scattered locations across the landscape. Both techniques have their advantages and disadvantages. Food larders are easy for a bird or rodent to defend but a raid or disaster could wipe out an entire food supply. Food stockpiled in this way tends to be kept for long periods of time (months or longer) and most birds that stockpile food in this way are colonial (as is the case with Red Headed and Acorn Woodpeckers). Scattered sites do not have to be defended as much as most items are well-hidden in unique locations and the loss of a few sites will not jeopardize the food supply. However, animals are more likely to forget items. Most of the birds and all squirrels in our area stockpile food in scattered locations rather than in a single location. Nuts and seeds are better candidates for long-term storage than fruits, or insect prey. Nuts and acorns may still be edible months after they are hidden, while meat or fruits could spoil if they are not retrieved in a timely manner. Warmer temperatures during the winter can cause food items to spoil according to this video about Grey Jays from Cornell Lab of Ornithology.

Learn more about hoarding and caching by visiting its article on Wikipedia. This is a good place to start and there are additional references that editors used on the bottom of each Wikipedia article. 

Animals that Cache Food 

In the Cape Fear Region there are a number of birds and mammals that store food for later use. All three of the squirrel species in our area store nuts and seeds during the autumn with Grey and Fox Squirrel using the scatter hoarding technique. In the interior of the Carolinas, the Eastern Chipmunk stores seeds and nuts in their dens before hibernating, while beavers, and most rat or mouse species will provision food in their homes. For birds, the main species that store food are members of the Corvid family like crows, ravens, and jays, two species of woodpeckers, nuthatches, chickadees and titmice. Loggerhead Shrikes, and possibly owls or hawks may temporally store food to feed young or hide it from competing species. Below is a list of birds and animals that routinely store food.

Crows and ravens may carry items for miles. 

Common Crow: Common Crows store a variety of food items throughout the year although they are most likely to hoard nuts from hickories, oaks, beeches, and chestnuts during the autumn. This species of crow lives in family units or colonies in forested areas and usually hides nuts and seeds in tree hollows, under stones, or in the ground. Crows may also hide meat, large insects, or food picked from waste bins to hide it from other birds. It is not clear if Fish Crows stores food as extensively as the Common Crow. The Common Raven also hoards food. 

Blue Jays often hoard feeder items for later use.

Blue Jay: Blue Jays readily stockpile nuts from oaks, hickories, beeches, chestnuts, and pines from late summer through winter. They also take large amounts of food from birdfeeders stocked with peanuts, sunflower seeds, or chopped tree nuts to hide in tree holes, crevices, or in the ground. Jays may also hoard during the summer. 

Loggerhead Shrike: Shrikes create larders by impaling their prey to thorny trees like hawthorn, or honeylocust or to manmade objects like barbwire and chainlink fences. These predatory songbirds often store grasshoppers, cicadas, small rodents, lizards, and other songbirds for later use or to feed young. Pairs fiercely defend sites from marauding crows, jays, or opportunistic mammals like raccoons or foxes. Birds of prey like owls and hawks may also temporally store prey. 

Red Bellied Woodpecker grabbing peanut as a Mockingbird guards the suet.

Red Bellied Woodpecker: The ubiquitous Red Bellied Woodpecker is a scatter hoarder like the Blue Jay with individuals or pairs storing nuts, seeds, large insects, and items from bird tables throughout the year.  Acorns, beechnuts, and hickory nuts are most likely to be stored long-term with the majority of items stored in the autumn and retrieved during the winter. Other items are hidden short-term to outsmart squirrels, crows, jays, or even agile nuthatches that try to plunder caches. Most items are wedged between bark, in crevices, or in human structures like telephone poles, wooden fences, or siding. 

Red Headed Woodpecker: The Red Headed Woodpecker is a colonial woodpecker that creates small larders near roost and nest trees. While this woodpecker does not create massive pantries of acorns like the Acorn Woodpecker out west, they do stockpile as many acorns, and nuts as they can find. This woodpecker will also store large insects, and small vertebrate prey items, as well as fruits for short periods of time. Items are usually wedged into bark, dead trees, or drilled holes in trees or decayed posts. Red Headed Woodpeckers will defend their hoards from other birds and squirrels.

Brown Headed Nuthatches can store large amounts of food in larders. 

Brown Headed Nuthatch: This nuthatch creates small larders that are scattered across several trees with pine seeds and other conifers seeds making up the majority of the stockpile.  Almost all items are wedged behind bark or in tree crevices and  manmade structures. As a colonial or gregarious species, this nuthatch is often seen in groups of 5-20 birds and may defend sites. Nuthatches often hoard sunflower seeds, peanuts, chunks of suet, or other items and will fly back and forth from feeders to save up food. They may do this to avoid competition with other feeder visitors or larger birds like woodpeckers. There is also interspecies competition between Brown Headed Nuthatches and Pine Warblers over pine seeds with the latter not known to hoard food. 

White Breasted Nuthatch: This ubiquitous nuthatch stores small amounts of food throughout  the year although it does not creates larders. Pairs or individuals may store nuts, seeds, or birdfeeder items in nearby trees, sides of houses, or even plant stalks in a garden or weedy field. Other food items are stored short-term to hide it from other songbirds.

Red Breasted Nuthatches are normally seen in Wilmington when conifer seeds are scarce up north.

Red Breasted Nuthatch: Like White Breasted Nuthatch, this small nuthatch usually hides seeds or nuts to avoid competition or as an insurance policy for rainy, snowy, or windy days. This bird also depends on conifer seeds and will venture outside of the boreal regions of Canada or the Appalachian Corridor when spruce, fir, hemlock or White Pine seeds are scarce. 

Chickadees often hide food from other birds and may move items several times. 

Carolina Chickadee: Chickadees will stockpile individual seeds, nuts, or insects over a short period of time during any month of the year. Chickadees may do this to hide food from other chickadees, or more aggressive nuthatches, titmice, and woodpeckers, or to ensure a steady food supply on rainy, windy, or cold days. Chickadees and titmice will often wedge items in crevices, plant stalks, bark, manmade objects, and even hanging planters. Since chickadees often hoard sunflower seeds from bird tables, there may be random sunflowers growing out of flowerpots, or other unexpected locations. 

Titmice are less likely to store up food and mostly do so in autumn.

Tufted Titmouse: Like Carolina Chickadee, except that titmice store food less prolifically and often to hide items from other birds. 

Grey Squirrels burry hundreds of nuts, creating new trees in the process.

Squirrels: Grey and Fox Squirrels will spend the summer and autumn stockpiling nuts, and seeds from various trees to prepare for winter. Since neither squirrel species (nor the Flying Squirrel) hibernates, they must ensure there is a supply of food through the winter. Squirrels burry nuts in soft soil or in out of the way spots like tree stumps, or crevices. Nuts and seeds are stored in scattered locations with hundreds of items hidden at a time. While many caches end up being pilfered by other squirrels, groups of crows, jays, or local Red Bellied Woodpeckers, there are more than enough food stored for a family of squirrels. Many items are forgotten, allowing new oaks, hickories, or other trees to sprout. Squirrels store up large amounts of birdseed as well, meaning that the majority of the items that local colonies raid from bird tables ends up being buried. This may be part of the reason why volunteer sunflowers, millet, corn, and milo plants spring up in gardens well-away from the bird feeders.  

Ecological Roles 

Oaks like these Live Oaks depend on squirrels and birds for seed dispersal.

Food caching can benefit animals by ensuring a steady food source for times of scarcity, or by keeping precious items safe from competitors. However, food stockpiles can also benefit the ecosystem in a number of ways. 

• Forgotten nuts by squirrels, crows, and jays can allow trees like oaks, hickories, beeches, and formerly the critically endangered American Chestnut to spread to new areas. Birds like jays, crows, and nutcrackers can can carry nuts very long distances.

• Cache raiding is a easy way for opportunistic birds or mammals to get food during the winter

• Stored food is very important for animals in the Far North such as Grey Jays, Boreal Chickadees, Common Ravens, and Northern Shrikes. Spoiled food larders due to warming temperatures could jeopardize winter survival or breeding success

• Stored items may also feed or shelter insects