What are these bubbles on the plants? Why does the field look black and burned? What wild tree flowers in December? Are all red mushrooms poisonous? What are these seed pods that grow on a vine? What are those tall yellow flowers? Is this brown snake a copperhead? What is Raleigh's rarest lettuce? What are those foam-like things on the plants?
The Nature Program is bringing some natural science to you by answering your questions about Raleigh's Nature Mysteries!
Do you have a Nature Mystery question? We'd love to hear from you!
Email questions and photos to WilkersonNaturePreserve@raleighnc.gov Look for more answers to Raleigh's Nature Mysteries coming soon!
Have you every noticed small balls of bubbles on flower stems or tree twigs? Do The bubbles sort of resemble spit? These bubbles are not produced by the plant itself. These bubbles are made by a group of insects appropriately called ‘spittlebugs’. Spittlebugs are in the insect order Hemiptera, or true bugs. This makes them closely related to cicadas, leafhoppers, and aphids.
In July or August, adult tree spittlebugs lay their eggs under bark, bud scales, or in needle sheaths of live trees. The teardrop-shaped eggs remain through the winter. The following spring the young, or nymphs, emerge. The nymphs have needle-like mouth parts used to pierce the plants to feed off of the juices within. As the nymphs feed, they excrete excess sap which is then forced out of their abdomen under pressure and mixed with air to create the spittle-like bubbles. They use the bubbles to cover themselves in to keep from drying out and protect them from predatory insects.
While there are a variety of spittlebugs, two of the most common in our area are the Pine Spittlebugs (Aphrophora parallela) which only produces one generation per year, and the Two-lined Spittlebug (Prosapia bincincta) which can produce two generations per year. Two-lined Spittlebugs prefer soft plant stems such as wildflowers and grasses. All adult spittlebugs are fairly small, typically less than a half-inch long. Their wings fold over their backs, and they have large eyes somewhat like a tiny cicada. When disturbed they readily jump or fly. Some species can jump more than two feet in the air! The adults also have piercing mouth parts that allow them to feed off of plants. They can often be found in tall weeds or grasses and sometimes appear under porch lights after dark. Spittlebugs are not harmful to humans or pets and usually to few and scattered to be harmful to the large plants on which they feed.
Next time you’re out walking, see if you can find evidence of nymphs in their bubbles especially on pine trees, or adults in the grassy meadows! You may even have these in your own backyard!
Why does the field look black and burned?
Recently a field at Wilkerson Nature Preserve was on fire. Don’t worry - it was intentional! Staff worked closely with the North Carolina Forest Service to plan a prescribed burn as a method to maintain the meadow. Prescribed fire is used in many natural areas to improve wildlife habitat, reduce exotic species, and promote rare native species and ecosystems, including in many parks around Raleigh. When done in a forest setting, prescribed burning also reduces the risk of a future uncontrolled fire by consuming potential fuels. However the procedure is not as simple as just lighting a match, and should only be done by those with prescribed fire training.
So, what is involved? In advance of a burn, staff evaluate the area to determine the boundaries of the planned burn site. Field prep is done which may include cutting paths around the boundary and sometimes through the middle of the planned area. This not only helps to contain the fire within the desired boundary, but also allows breaks within the area. These fire breaks are used to slow the fire down as it crosses the field, to keep it manageable.
Weather forecasting has a large part in planning a prescribed burn. A number of weather-related factors must fall in specific ranges. For example, if it is too humid it may be difficult to light the fire. If there is not enough wind the smoke will not be carried up and away, however if there is too much wind it would be too dangerous to start a fire. Wind direction plays a part as well – which way will the wind carry the smoke? Planners need to be mindful of not creating smoke-related hazards in the community around the planned burn. Using these factors, staff look at the forecast and designate days that might fall within the safe ranges. The final decision that it is safe to burn is not made until the morning of the planned burn, and in some cases can be called off due to a shift in any of those factors, even after everyone is gathered and ready.
On the days of Wilkerson Nature Preserve’s burn this March, these factors all remained in their safe zones, and the North Carolina Forest Service arrived with personnel and safety equipment to survey the planned area one last time. A test burn was performed to be sure conditions were still favorable on the ground. The test burn went well, and the field was lit by a torch in a systematic approach, from one end to the other, burning into the wind rather than with it. While keeping constant communication via radios, the team worked to back-burn segments of the field, so as the fires approached they met with an area that had already begun burning- therefore reducing the available fuels and allowing the fire to maintain a controllable level. Water trucks and hoses were at the ready, but only used at the fire boundaries. Once the fire had moved through the planned area, a few remaining hot spots were observed for potential dangers as they quickly died out. As we have seen after past prescribed burns, after the fire is complete, nature soon takes its course, and new healthy plant sprouts appeared within a week – after a few months’ time it will be difficult to find any trace of black ash under the new carpet of fresh, green grasses and wildflowers.
What wild tree flowers in December?
We think of Spring as the season for flowers, especially flowering trees, and shrubs.
Fall is when we expect colorful leaves on our trees, not flowers, and most people would never go looking for wildflowers in December. But there is one exception to this rule growing wild in Raleigh’s forests – the American Witch Hazel (Hamamelis virginiana), also called “Winterbloom,” for its unusual flowering habits.
American Witch Hazel is a native shrub or small tree with a strange name and an even stranger flowering season, blooming mostly from late October into December.
Each Witch Hazel flower has four narrow yellow petals up to about 1 inch long, and because the flowers often appear in clusters along the branches, when in bloom, the whole tree can appear dotted with bright yellow that stands out against the winter-bare branches.
The odd name “Witch Hazel” comes from the Old English word “wych” or “wice,” meaning “weak.” This word was used in old names for several European trees with “weak” or flexible branches, and Witch Hazel branches are pretty flexible. Our word “wicker,” referring to basket-work made by bending flexible strips of wood, also comes from this word root.
The “Hazel” in “Witch Hazel” refers to the similarity of shape between Witch Hazel leaves and the leaves of Hazelnut shrubs. True Hazelnuts grow wild around Raleigh, but they do not make clusters of yellow late-fall flowers, so a blooming Witch Hazel is easy to distinguish from a Hazelnut.
Witch Hazel does produce a fruit shaped something like a small, yellow-brown nut, which you can usually find on Witch Hazel branches near the flowers. When the fruit is fully ripe it will suddenly “pop” open and throw its small seeds through the air several feet or yards away, where they may sprout and add to a growing Witch Hazel patch. The name “Snapping Hazel” refers to this explosive method of seed dispersal.
The seeds of Witch Hazel have valued food for birds and small forest mammals, and the leaves and flowers provide food for many insects, including butterfly caterpillars and pollinators.
The leaves and twigs of Witch Hazel are also eaten by deer, which can make Witch Hazel difficult to grow in areas with high deer populations unless protection is provided until the plant is tall enough to have branches growing higher than deer are able to reach.
The most common human use for Witch Hazel today is as the source of the Witch Hazel extract found in some cosmetics and first aid supplies. This extract is produced by boiling Witch Hazel twigs. Witch Hazel extract has a long history of use for its anti-inflammatory properties, especially when applied to the skin.
Look out for a yellow-flowering shrub or small tree while enjoying Raleigh’s forests this December – you may find a Witch Hazel, Raleigh’s own wild “winter bloom”!
Are all red mushrooms poisonous?
Fall is a great time to look for mushrooms in the forest, and bright red mushrooms are incredibly colorful and easy to spot. Unfortunately, some people think all red mushrooms are poisonous, but the truth is more complex. Some common red mushrooms are poisonous, while others are not. In addition, DNA evidence shows that North American mushrooms that may look almost identical to European or Asian mushrooms may be unique North American species. This explains why their taste and toxicity are different from what looks like the "same" mushroom from another continent.
While eating wild mushrooms carries risks, we can all safely enjoy these mushrooms' bright colors the same way we enjoy colorful wildflowers – without picking them!
A few red forest mushrooms to look for:
Red Russala is often labeled with the name Russala emetica, a common red European species. There are over 100 red Russala species found worldwide, which may require microscopic examination to tell apart. In general, Red Russala species have a pinkish or reddish cap with white gills underneath and a white stem with no “bulb” or skirt-like “veil” attached.
Russala emetica is often called “the sickener” because eating it raw frequently causes nausea, diarrhea, and vomiting. However, it is not a deadly mushroom, and there are preparation methods traditionally used in Europe that can reduce the toxins to make it more edible. American Russalas also share these toxic properties to varying degrees.
Although toxic to humans when raw, many animals enjoy eating Russala mushrooms, including squirrels, snails, and insects.
Red Chanterelle (Cantharellus cinnabarinus or similar species) is a smaller mushroom, where both the stem and the cap are all red-orange, including the gills. Like other chanterelles, the gills reach down the stem somewhat, and there is no “bulb” or skirt-like “veil” attached. Chanterelles are generally non-toxic, but look-alike “false chanterelles” can cause digestive upset and other unpleasant reactions in humans.
Caesar’s mushrooms, or the European species (Amanita caesarea), is well known as edible, and the common American species (Amanita jacksonii) is very similar in appearance. However, as an Amanita, it is also a close relative to some of the world’s most deadly mushrooms, including the “death cap” (Amanita phalloides) and “destroying angel” (Amanita virosa).
The pale white gills on many deadly Amanita mushrooms help distinguish them from Caesar’s Mushrooms, including the American Caesar, which has yellow gills. But with hundreds of Amanita species, positive identification requires experience and always carefully checking multiple features.
Unfortunately for Americans, while the American Caesar’s mushroom is not poisonous, it also seems to lack much of the flavor that makes the European Caesar’s mushroom so appealing. Wildlife still enjoys eating them (including deer and box turtles), and we can enjoy seeing their large, colorful, red-orange caps when they appear in our forests.
Even though some colorful forest mushrooms really are poisonous, none of our mushrooms are dangerous to humans if simply touched. Poison mushrooms are not like poison ivy! There’s no reason to be afraid of any of our wild mushrooms as long as you’re not eating them.
A forest filled with mushrooms provides fall food for many creatures, and Eastern box turtles are one forest animal that especially enjoys eating mushrooms, including many toxic kinds. Enjoy seeing and identifying the bright colors of fall’s mushrooms during a forest hike!
What are these seed pods that grow on a vine?
Many people recognize the spiny-looking pods full of fluffy seeds that fields of common milkweed (Asclepias syrica) growing around Raleigh produce in the fall.
But another Raleigh plant also makes bumpy seed pods full of fluffy seeds, except this plant is a climbing vine.
This vine also has milky-white sap in its stem, just like our common milkweed, and for this reason, it is called “Milkvine” (genus Matelea). Like milkweeds, many Mmlkvines produce clusters of interesting flowers attractive to pollinators. Many milkvine flowers have five purple petals, making their flowers look a bit like a cluster of purple starfish.
Milkvine is in the same family as our common milkweed but not the same genus, so milkvines are not considered “true” milkweeds. But because milkvines are in the milkweed family, milkvines are sometimes called “climbing milkweeds”.
Monarch butterflies are famous for needing Milkweed leaves to feed their caterpillars. Despite not being “true” milkweed, milkvine leaves are another food plant that Monarch caterpillars can and do use. Unfortunately, milkvine plants are rarely available for sale, and even in the wild, many milkvines have become uncommon or rare.
Several milkvine species occur naturally in North Carolina. In Raleigh, glade milkvine (Matalea decipiens) is one to look out for. This plant is listed as "critically imperiled” in several states, including Virginia, and it is tracked on the North Carolina Natural Heritage Program’s Rare Plant List. It can be found in some of Raleigh Parks' nature preserves.
Carolina Milkvine (Matalea caroliniensis) is another, more common, local milkvine species, as is anglepod (Gonolobus suberosus), which grows pods with ridges instead of milkweed-like bumps or spines. Both of these milkweed-family species produce similar 5-petaled flowers, but their petals are shorter compared to those of glade milkvine, and their flowers are often more greenish rather than purple.
Milkvines are perennials that live for many years, growing back from their root after their vine dies to the ground each winter. Part-shade with some direct sun is ideal for them, but they are vulnerable to being eaten by deer. Once established, milkvines can climb to heights of over 6 feet and produces many flower clusters and pods.
So if you see a spiny milkweed-like pod dangling from a vine this fall that looks like it belongs on a milkweed, that’s a milkvine – another Monarch-friendly native plant.
What are those tall yellow flowers?
Sunflowers is the ‘star’ flower of mid-summer gardens. Still, in late September, a different kind of tall yellow flower catches the attention of many people in natural areas around Raleigh.
Often mistaken for planted sunflowers, these golden fields are entirely wild and are colored by the blooms of a native plant called “Yellow Crownbeard” (Verbesina occidentalis).
Crownbeard is a native member of the Sunflower Family. Like sunflowers, Crownbeard flowers are a valuable nectar source for pollinating bees and butterflies – and the timing of their blooms is perfect for the migrating Monarchs that pass through Raleigh in September. Also, like sunflowers, after flowering, Crownbeard produces clusters of nutritious seeds (they look exactly like tiny sunflower seeds), which feed many songbirds as they prepare for winter.
Although a field of Crownbeard is beautiful, the individual flowers are small and have an irregular appearance, and when examined closely, you will find that not all Yellow Crownbeard plants bloom with the same shade of yellow.
For unknown reasons, some Yellow Crownbeard plants have pale “lemon-yellow” flowers, while other plants have deeper “egg-yolk-yellow” colored flowers.
On any Crownbeard plant, all the flowers will be either “lemon-yellow” or all “egg-yolk-yellow” – never mixed. But plants of both colors may grow side-by-side in the same field, with the “egg-yolk-yellow” color being the most common.
Yellow Crownbeard only blooms for a short time – by October, these flowers will have faded away, and the loose petals can be knocked off earlier by rough weather.
So enjoy Raleigh’s all-natural late-September wildflower show! They don’t last long, but they are a much-valued resource for fall butterflies and early-winter birds.
If you’re thinking of growing Yellow Crownbeard in your yard, this plant has one more valuable feature – deer don’t like to eat it!
Is this brown snake a copperhead?
Raleigh is called the “City of Oaks”, but it could be called the “City of Reptiles”. We have many species of snakes, lizards, and turtles that live in backyards and forests throughout the city, but most attention goes to the one native reptile found in Raleigh that is venomous to humans – the copperhead.
The good news is, most snakes you’ll see in Raleigh are not copperheads. Many of Raleigh’s snake species are naturally small, brown-colored, and rarely grow much more than 1 foot long. These common “little brown snakes” are sometimes mistaken for “baby copperheads”.
Here’s how to know if the snake in your backyard is a Copperhead:
Does it have a brown-banded body (and maybe a bright yellow-green tail)? It could be a baby copperhead.
Does it have a brown body (but not with thick, dark bands) with a brown tail? It is not a baby copperhead.
Let’s meet some of Raleigh’s most common snakes:
“Brown Snake” (Storeria dekayi)
The brown snake is possibly Raleigh’s most common snake. They are small and brown with little scattered dark spots on their back and a whitish-grey belly. They are a tiny, completely harmless cousin to the rat snake.
Red-bellied Snake (Storeria occipitomaculata)
Also very small and brown and similar to the brown snake, the red-bellied snake has a belly that is a striking red or orange.
Worm Snake (Carphophis amoenus)
Also brown colored and frequently found in mulch or dirt, the worm snake’s belly is noticeably pinkish.
Smooth Earthsnake (Virginia valeriae)
These uncommon small, plain brown snakes have slick, glossy scales and a grey belly.
Rough Earthsnake (Haldea striatula)
These snakes are often found near rocks and are very similar to Smooth Earthsnake, but the scales of Rough Earthsnakes each have a ridge or keel down their middle that can be seen when they are examined closely.
All these little brown snakes can be found in Raleigh backyards. It is also common in summer to find small young of other larger snake species, such as baby rat snakes, baby racers, and baby water snakes. While some of these snakes may have a brown body with bands when they are young, none of them have a bright yellow-green tip on their tail the way a baby copperhead can.
Take some time this summer to get to know the many tiny, helpful, harmless snakes that call Raleigh home!
What is Raleigh's rarest lettuce?
Some lettuces we know well…iceberg, romaine, red-leaf, and Boston bibb are salad bowl favorites. But all our garden lettuce varieties (Lactuca sativa) came from Wild Lettuce (Lactuca spp.) ancestors.
All Wild Lettuces are edible, but some taste much better than others. Taste aside, Wild Lettuces are valuable for crossbreeding with our Garden Lettuce varieties, most often to improve disease resistance. Recent studies have also found that Wild Lettuces have higher Vitamin C levels than Garden Lettuce, and there is potential to use Wild Lettuces to improve the nutritional value in Garden Lettuce through crossbreeding as well.
The closest ancestor to our Garden Lettuce is the common ‘Prickly Lettuce’ (Lactuca serriola) which is often seen growing as a ‘weed’ on Raleigh roadsides. Other Wild Lettuces are commonly found in Raleigh’s more natural habitats, including Canada Lettuce (Lactuca canadensis) and Woodland Lettuce (Lactuca floridana).
But there are some Wild Lettuce species that have become very rare in modern times – the rarest may be the Red Wood Lettuce (Lactuca hirsuta).
100 years ago Red Wood Lettuce was a more common wildflower – that was how it was described in the book “Wild Flowers Every Child Should Know” by Vassar College biologist Frederic Stack in 1909. The tall red-purple-colored stems and clusters of small reddish-yellow flowers would make it a colorful sight in an open woodland glade.
But since those days red wood lettuce has almost vanished – in North Carolina, only 1 plant has been collected by scientists in the last 50 years (from Robeson County in 2010)!
Even finding one red wood lettuce plant in NC in 50 years is better than some other states – in Maryland and Connecticut it is believed to have gone extinct. In many other states, it is legally listed as “Endangered” or “Threatened”.
Why did red wood lettuce disappear? We don’t know, but it is highly edible. Rising deer populations in recent decades across the Eastern United States have impacted many highly edible wild plants.
For years the staff at Annie Louise Wilkerson Nature Preserve have searched Raleigh for a living Red Wood Lettuce without finding any. But plants have an amazing ability to hide – they can sleep as seeds in the soil, sometimes waiting years to grow – and deer cannot destroy sleeping seeds until they are triggered to sprout.
As last hope to revive long-lost plants, a 1/10th acre piece of land at Wilkerson Nature Preserve was fenced-off completely from deer in 2020, and then burned with help from the NC Forest Service in March of 2021.
Chemicals in smoke have been proven in laboratory experiments to trigger germination in Lettuce seeds. Shortly after the 2021 controlled burn, a baker’s dozen of 13 Red Wood Lettuce plants appeared inside the fenced area! The fencing kept deer from eating the tender young sprouts, and by mid-summer, several Red Wood Lettuce plants at Wilkerson were producing flowers and seeds.
Biologists from several state agencies have since visited these plants, and specimens are being prepared for our regional University collections. The life cycle of Red Wood Lettuce is to die after producing seeds, so some new seeds are being saved, while other seeds are being allowed to fall back to the soil inside the fenced area.
We do not know how long the Red Wood Lettuce seeds had been sleeping in Wilkerson Nature Preserve’s soil. Some wildflower seeds have been proven to survive in the soil for 100 years or more. How long these seeds were waiting here is a mystery.
Thanks to deer protection and a carefully planned fire, visitors to Wilkerson Nature Preserve this summer can take a trip back in time, to the long-ago days when the rare Red Wood Lettuce was still a “Wild Flower Every Child Should Know”.
What are those foam-like things on the plants?
As you walk through the meadows in many of our parks you’ll notice that many of the plants have lost their leaves and have turned brown for the winter. Upon further inspection, you may discover that some of them have small foam-like structures on them. These structures are not part of the plant itself- these are praying mantis egg sacs, or ootheca.
Mantids are important predators throughout the summer eating almost anything, including each other. Many of the insects consumed by mantids are common pests, such as grasshoppers and mosquitoes. As fall sets in the mantids mate and the females find a vertical surface to lay her eggs. This could be on stems, twigs, rocks, fences, or buildings. The eggs are laid before the first frost, and then the female dies. Each ootheca contains dozens to hundreds of eggs that survive the winter because of the outer foamy insulation they are contained in. The young begin to emerge when the temperatures are warming in the spring. It’s important not to bring the egg sacs indoors during the winter, as it will simulate spring and cause the young to emerge too early. Even if they were released outdoors, the young cannot survive the winter once they’ve emerged.
The most commonly seen species of mantids in North Carolina are the Carolina Mantis (Stagmomantis Carolina) and the Chinese Mantis (Tenodera sinensis). Of course, the Chinese mantis is a non-native invasive species, however, it’s usually easier to locate the oothecas for this species. The oothecas for Chinese mantids tend to be rounder in formation and more often seen on twigs. During a short walk around Wilkerson’s pond the other day I located a handful of them fairly easily.
Carolina mantid eggs are smaller and look similar to a fossilized trilobite. These are more often found on trees, buildings and fences- but if you have a keen eye you can also find these on twigs and branches.