Where Insects Fear to Tread

There is no exquisite beauty …without some strangeness.

~Edgar Allan Poe

Part two of our quest for carnivorous plants took us first to the Green Swamp, a well-known NC Nature Conservancy preserve site in Brunswick and Columbus counties. It was getting late in the day, so we went straight to the main access point, a small parking area next to a borrow pit along Hwy 211. We hiked in along the trail, through a short stretch of dense pocosin vegetation, and out into the open longleaf pine savanna.

Longleaf pine savanna, Green Swamp

Longleaf pine savanna in the Green Swamp (click photos to enlarge)

What you find here often greatly depends on the fire regimen – the year after a burn can produce spectacular wildflowers and make it much easier to see any in bloom. From the looks of it, I am guessing it may have been over a year since this particular tract was burned, but we could see some scattered spots of color poking above the clumps of wiregrass, especially along the pocosin edge.

Gras pink orchid

Grass pink orchid, Calopogon sp.

In addition to insect-eating plants, these pine savannas are well-known for their gorgeous orchids. Calopogon comes from the Greek words meaning beautiful beard, and refers to the bushy, yellow protuberances on the lip of this delicate orchid. These are designed to attract pollinators, thinking there might be a pollen or nectar reward, but it is a deception. The lip of the flower is hinged at the base, and when an insect lands, the lip drops and traps the insect among the flower parts, forcing it to wriggle its way out, and, in the process, hopefully pollinating the flower.

Butterwort

Yellow butterwort, Pinguicula lutea

Scattered along the edges of the savanna are small, bright yellow flowers of a carnivorous species, the yellow butterwort.

Butterwort leaves

Basal rosette of a butterwort

The business end of a butterwort lies at the base, where a tight cluster of sticky leaves serves to trap small insects by means of tiny stalked glands covered in mucilage. Other glands release digestive enzymes to help dissolve the soft tissues of the prey, with the nutrient-rich juices being absorbed by the leaf to supplement its nitrogen supply in this nutrient-poor environment.

Sundew

Pink sundew, Drosera capillaris

A similar, but more active strategy, is employed by another insect-eater, the sundews. Tiny rosettes of red leaves covered in what look like dew-covered hairs dot the moist soil in the savanna, especially any place that is muddy along a trail or ditch.

Sundew with prey

Close-up of a sundew leaf with a trapped insect

When a potential prey touch the stalked glands, it gets stuck in the “goo”. Adjacent tentacles move toward the prey, further entrapping it. Digestive enzymes are released and the rest is history.

We finally had to head back to camp, but a good day of carnivorous plant exploration with sundews, two species of pitcher plants, butterworts, two species of bladderworts, and some Venus flytraps. The next day would prove to be even better.

Longleaf pine savanna Holly Shelter

Longleaf pine savanna in Holly Shelter

I had heard about Holly Shelter Game Lands for many years, but never managed to visit until now. It consists of over 63,000 acres of mixed forest, pocosin, and other wetlands in Pender County. Since it is turkey season, we were advised to visit on Sunday when there is no hunting. We drove along miles of dirt roads to several spots recommended by a friend for their plant diversity.

Carolina laurel

Carolina wicky, Kalmia carolina

Horse sugar

Horsesugar, Symplocos tinctoria

A few small shrubs adding splashes of color in the longleaf forests, including a Coastal Plain relative of mountain laurel, Carolina wicky (also known as Southern sheepkill). Small starbursts adorn another savanna shrub, horsesugar (aka sweetleaf).

Holly Shelter oitcher plants

Small pond at Holly Shelter surrounded by yellow pitcher plants, Sarracenia flava

Our first stop was amazing – hundreds of yellow pitcher plant flowers came into view as we approached a small pond. There was also the bright green of the emerging new leaves, so it was a perfect time to view this species.

Pitcher plant leaf before opening

An unopened pitcher leaf

It is easy to forget that in all of these carnivorous plants, it is the highly adapted leaves that are the trapping mechanism. In the case of the yellow pitcher plant, the leaf blade usually elongates a foot or more before the top splits open to form the deadly pitfall trap.

Pitcher plant opening

A leaf just beginning to split to form the pitcher

This pitcher has a hood (or lid) and usually has red veins that serve as nectar guides for potential prey, luring them deeper into the trap.

Fly going into pitvher plant

An open pitcher with an unwise fly

The trap is a simple one – lure your victim with nectar, a sweet reward concentrated along the rolled lip and down into the upper edges of the trap. Once inside, the walls of the pitcher change texture and become very slick, causing the insect to fall into the tube. Below the slippery zone, the walls have rows of down-ward pointing hairs that inhibit an upward escape. As the insect gets farther down into the trap, the tube narrows, making it more difficult for flying insects to use their wings to escape. Digestive enzymes at the base of the trap all but ensure the fate of the hapless insect.

Pitcher plant prey (2 pitchers)

Contents of two pitcher plants back at the NC Botanical Garden

A popular activity at work is for students to dissect old pitchers (last year’s leaves) and examine what the plant had for dinner. The enzymes only dissolve the soft tissues to release the needed nutrients, so the hard parts of prey remain – an assortment of wings, legs, and exoskeleton pieces. Coworkers gathered the insect parts from two pitcher plants in the Garden’s collection for the photo above: several moths (left side of photo); a cluster of flies (upper right); a wasp (top); some small beetles (lower right); and an assortment of unidentifiable wings, legs, and parts. A large amount of fine dust-like material from the trap is not shown in this picture. I need to collect a few dried pitchers from native habitats and see what the locals have been eating for comparison, but I have a feeling the menu could be similar based on that fly photo above. It was about to make a culinary misstep.

Purple pitcher plant

Purple pitcher plant, Sarracenia purpurea

Purple pitcher plants lack a lid and their pitchers usually contain rainwater. Prey fall into the pitcher and drown. Ironically, there is a species of mosquito, Wyeomyia smithii, whose larvae live in these pitcher plants and feed on the microscopic community that exists in the water.

Hybrid pitcher plant

Possible hybrid pitcher plant

We did see a few pitcher plant clumps that looked like hybrids between the purple pitcher plants and the yellow. The pitchers look like the S. purpurea, but are much more elongate, like an S. flava. The flowers also seem to be a combination of the colors of the two species – both maroon and yellow tints.

Sundew intermedia

Spoonleaf sundew, Drosera intermedia

Along the path were large numbers of the pink sundews we had seen in the Green Swamp, but the edge of the pond had another species. The spoonleaf sundew is more upright in growth form and seems to do well extending out into the water’s edge.

Sundew close up

A tiny insect trapped in the sticky goo of the sundew

I leaned down for a closer look and could see more victims that had fallen for the glistening droplets that adorn these deadly tentacles.

Purple butterwort  flower and base

Blue butterwort, Pinguicula caerulea

The Holly Shelter sites held two more species of butterwort – the blue and the correctly named small butterwort. The latter (which I failed to get a good photo of it turns out) has a pale, almost white flower, with a short flower stalk and a tiny rosette of leaves.

Purple butterwort group

Blue butterworts were very common

The larger, blue butterworts, were quite common and often occurred in patches of twenty or more individuals, scattered about the various sunny locations we visited.

Venus flytrap cluster

Venus flytraps, Dionaea muscipula, and a small purple pitcher plant

The Venus flytraps were amazing, as always, and abundant. Melissa mentioned all of these carnivorous plants in a recent post about one of her museum trips, so I won’t go into all the details of this, “one of the most wonderful plants in the world”, but I will share a few interesting tidbits.

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Close-up of a flytrap leaf, showing the trigger hairs

The trap is a modified leaf and has 2 to 3 trigger hairs on each lobe of the trap. Two triggers must be touched in succession within about 20 seconds for the trap to “spring” (or one trigger twice). Closing in less than a second, the Venus flytrap is one of a group of very few plants capable of rapid movement (other local rapid movement plants include Eastern sensitive briar, Mimosa macrophylla, and bladderworts, Utricularia sp.). The fleshy “teeth” along the edge of the trap mesh together to form a closed cage around any prey (usually crawling insects and spiders). The whole trap squeezes together more tightly when the prey struggles. Enzymes are then secreted by minute glands on the inner surface of the lobes and the victim is digested over the next few days. Afterward, the trap reopens, awaiting its next target (each trap can only spring a few times before that leaf dies).

Venus flytrap

Emerging flytrap leaves

The name, Venus flytrap, refers to Venus, the Roman goddess of love. The genus, Dionaea, refers to Aphrodite, the Greek goddess of love and the daughter of Dione. The species name, muscipula, is Latin for mousetrap. It really is remarkable that the only place this amazing plant is naturally found is in about a 70-mile radius of Wilmington, NC.  This trip proved to be one of strange beauties and incredible adaptations, and is definitely one we will do again.

Bay Watch

Find one, and you’ll find yourself closer to the heart of what a Carolina Bay can be: an island of wildness in a world largely tamed, a few acres of the primeval past passed over by progress.

~T. Edward Nickens

The North Carolina Botanical Garden has an exquisite collection of carnivorous plants, and they are always a favorite stop on my programs. This encouraged me to revisit these mysterious beauties in their natural habitats in southeastern North Carolina. We got a few tips from our friend, Jerry, on some of the best locations, and headed out last weekend in search of insect-eating plants. This is part one of that exploration – the part we explored by kayak.

Jone Lake

Afternoon paddle on Jones Lake (click photos to enlarge)

Our home for the weekend was the campground at Jones Lake State Park, a beautiful park centered on one of the many Carolina Bays that dot the landscape in this part of the state.

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Google Earth view of the area showing a small portion of the estimated 900 elliptical Carolina Bays found in Bladen County.

These unique land forms attracted attention after the onset of aerial photography in the 1930’s, when thousands of ovals of varying size (there are an estimated 500,000), aligned in a northwest-southeast direction, could be seen dotting the Atlantic Coastal Plain from New Jersey to Georgia. The greatest concentration was in the Carolina’s. That fact, combined with their usual dominant vegetation of various bay trees, gave them their name. Few open water Carolina Bays remain, but even those that have been drained and developed, or have naturally filled with vegetation, are still visible as elliptical shapes in satellite images like the one above.

Many hypotheses have been proposed on the origin of Carolina Bays (including that they were formed by impacts of a meteor shower), but no single explanation is universally accepted. Many scientists now subscribe to the so-called oriented lake theory. It suggests that as the ocean retreated thousands of years ago, shallow pools of water remained throughout the Coastal Plain. Prevailing winds and resulting waves from the north elongated the ponds into their present elliptical shape. Whatever their origin, there is a large concentration of these bays in the Bladen Lakes area, and, fortunately, many are now preserved as state-managed lands.

Jones Lake sunset 1 Lake sunset

Stunning sunset from our kayaks on Jones Lake

Jones Lake sunset 1

Cypress tree with Spanish moss at sunset

Our first evening, we paddled our kayaks around the lake and enjoyed a spectacular sunset all to ourselves among the scattered cypress trees along the eastern shoreline.

Melissa paddling Horseshoe Lake

Melissa paddling Horseshoe Lake

The next morning we headed over to nearby Horseshoe Lake (aka Suggs Mill Pond). It is an aptly named shallow lake that is part of Suggs Mill Pond Game Lands, managed by the NC Wildlife Resources Commission. Suggs Mill Pond is an old millpond formed by damming a large peat-filled bay.

Horseshoe Lake wide angle

A sea of yellow pitcher plant flowers in the wetlands at Horseshoe Lake

It is spectacular this time of year as it contains thousands of yellow pitcher plants, Sarracenia flava. Their unusual flowers can be seen stretching across the wetlands along the lake edge.

Pitcher plants along shoreline

Yellow pitcher plants in bloom along the shoreline

The new growth leaves that will form the pitchers are also visible, with many already opening into the deadly traps that will consume an array of insect prey over the next growing season.

Dragonfly shed on pitcvher plant flower

Shed skin of a dragonfly where it transformed  from an aquatic nymph into the winged adult

Sometimes the plants can serve as a place of “birth” instead of death. There were large numbers of dragonflies and damselflies on the wing and ample evidence of their amazing transformation from underwater predator to aerial acrobat scattered about on any upright surface sticking above the water – even on the flower of a pitcher plant.

Lily pads on Horseshoe Lake

White waterlily pads dotted the lake surface in many areas

One of the dominant plants in the lake was the beautiful white waterlily, Nymphaea odorata. The cleft leaves dot the surface with an array of colors, from green to red, and provide a place for all manner of creatures to sit upon the water.

cricket frog

Southern cricket frog, Acris gryllus

The repeated gick-gick-gick calls of Southern cricket frogs could be heard everywhere we paddled, along with the occasional katunk-katunk-katunk of carpenter frogs.

Lilypad forktail male

Male lilypad forktail damselfly

Delicate damselflies glided along our path, pausing briefly in their pursuits of prey, or each other, to rest upon a lilypad. The lilypad forktail is aptly named, as it almost always rests on lilypads, and characteristically touches the tip of its abdomen to the leaf surface.

Lilypad forktail imm female

Immature female lilypad forktail

Adult males are brilliant blue with dark thoracic stripes. Adult females are lighter blue and immature females are a bright orange.

white water ilies

The flowers of white waterlily

The elegant flowers of the white waterlilies always tempt me to lean just a bit too far over the side of my canoe or kayak in order to capture their pleasing low-angle reflection.

Common grackle

Common grackle

We spotted several species of birds on the lake, including a green heron, red-shouldered hawk, northern parula warblers, Eastern kingbirds, wood ducks, mallards, and several common grackles busy setting up nest sites. This striking fellow allowed me to drift close enough to his perch to catch his iridescent colors…

Common grackle showing nictitating membrane

Common grackle showing nictitating membrane

…and to see his “third eyelid”, the nictitating membrane.

bladderwort

Bladderwort flowers

In addition to the thousands of pitcher plants, another carnivorous plant species was incredibly abundant at this location – bladderwort, Utricularia sp.

Bladderwort mass

Bladderworts, showing vegetative portions beneath the water surface

These mostly aquatic plants (there is a terrestrial species that occurs in moist sandy soils) have delicate flowers perched on slender stalks above the water, but the bulk of their biomass is beneath the surface. Scattered among the feathery vegetative portions, they have minute bladder-shaped organs with trap doors that can suck in tiny invertebrates that come in contact with the trigger hairs. Some areas of the lake had so much of this plant that it was like paddling through pudding at times as the vegetation clung to your paddle with every stroke. But, Horseshoe Lake is, nevertheless, a truly magical place, especially by kayak or canoe. Part 2 of our quest for the carnivores of the plant kingdom in the next post.

Catching Gnats and Plucking Lichens

More than with most species of small birds, the attention and interest of the observer center about the nesting habits of the blue-gray gnatcatcher because of the great beauty of its nest.

~Francis Marion Weston, 1949

One of my favorite spring arrivals is the plucky little blue-gray gnatcatcher. It is tiny, but bold. It looks a bit like a tiny mockingbird, but builds a nest like a large hummingbird. My friend, Mary, found a nest at the Garden recently and emailed me where to look as I prepared for a program. I never did find that one (they are often very well camouflaged on a branch). But, a week later, as I was leaving work, I heard the familiar “Steeve” call, looked up, and saw one fly into a small tree. I got out my binoculars, and was pleased to see a nest in progress.

Blue-gray gnatcatcher nest empty

Blue-gray gnatcatcher nest (click photos to enlarge)

A few evenings later, I brought my camera and spent some time watching this industrious duo go about the business of finishing what is certainly one of nature’s most beautiful nests. By this time, it looked like the nest was nearing completion, but the gathering of materials, and fine-tune adjustments, continued for over an hour as I watched.

Blue-gray gnatcatcher with spider silk on bill

Female bringing in spider silk

The nest is a deep (about 3 inches) cup about 1.5-2 times the size of a ruby-throated hummingbird nest. Otherwise, they look almost identical – a somewhat high-walled, elastic nest covered on the outside with lichens and held together with spider silk. The inside is lined with soft materials like plant down, hair, and fine feathers.

Blue-gray gnatcatcher in nest 2

Male checking the feel of the nest

As I watched, both adults were busy contributing to the efforts. During the breeding season, the male blue-gray gnatcatcher (photo above) can be distinguished from the female (photo below) by the presence of their black forehead and supercilium (a stripe that runs from the base of the birds beak and above its eye). The female’s head is plain gray.

Blue-gray gnatcatcher in nest 3

Female inspecting the progress

I had my big telephoto plus a teleconverter, so I was well away from the nest. The birds chose a very busy location for their activity, right next to a road and walkway that is popular with Garden visitors, so I don’t think they minded me watching them.

Blue-gray gnatcatcher in nest 5

Male placing a lichen

There were times when nothing happened at the nest for 10 minutes or so, then there were bursts of activity with a bird bringing in materials (especially crustose lichens – they look like lichen cornflakes) every minute or so. The usual routine was to fly into  a branch next to the nest, pause, then hop into the nest and place whatever material was brought in. Then there was often some fine-tuning, placing the lichen just so, inspecting it for a second, and then off again. Time spent in the nest on any one visit was usually less than 20 seconds. References say it takes about a week to complete a nest, but I think this pair could do it much faster based on what I saw.

Blue-gray gnatcatcher singing

Male singing

Blue-gray gnatcatcher preening

Male preening

In between nest-building activities, the pair would pause for some singing, preening, or the important duty of nest protection. I am a bit worried about this particular nest, since it seems in a more open location than many I have seen. There are a lot of hazards to any nesting bird, especially one so tiny. I witnessed a few bouts of territorial defense as this pair chased after a crow and a pair of blue jays that flew through their air space. And a pair of brown-headed cowbirds received a lot of attention when they perched within 50 feet of the nest. Both adults repeatedly dive-bombed the cowbirds, who seemed uninterested. They eventually flew off, and nest building resumed about 5 minutes later.

Blue-gray gnatcatcher pressing down in nest 1

Shaping the cup

The final stage of nest building is refining the shape of the cup. This is something they put their whole body into…the adult plops down into the nest with just their head and long tail (the tail accounts for about 45% of the total body length) visible and pushes against the sides of the nest, shaping it as they rotate their body around, flexing the sides until it is just right.

Blue-gray gnatcatcher pressing down in nest

Putting your whole body into getting the shape just right

At times, I could barely see their head at all, with just the slender bill projecting above the lichen wall. I checked on the nest the next few days and saw no activity, so I figured they had completed construction. And now, I see the female sitting in the nest for long periods of time, so I assume she is incubating her eggs. I will keep you posted on their progress.

Unfurling

Only spread a fern frond over a man’s head and worldly cares are cast out, and freedom and beauty and peace come in.

~John Muir

Before there is a fern frond, there is a fiddlehead. The curled tip of an unfurling fern frond resembles the curled ornamentation (called a scroll) on the end of a stringed instrument, such as a violin. It is also called a crozier (or crosier), from the curved staff used by bishops, which supposedly has its origins in the shepherd’s crook.

It is a ritual repeated every spring, and one that always catches my eye…the beautiful and detailed unfurling of the frond, starting at the base of the leaf blade and progressing outward and upward. It is one of the simple delights of spring.

A gallery of ferns unfurling from the woods behind our house, to the NC Botanical Garden to the Green Swamp…

Fern fiddlehead

Southern shield fern fiddlehead (click photos to enlarge)

early Cinnamon fern

Cinnamon fern

Cinnamon fern fiddlehead

Cinnamon fern fertile frond

Cinnamon fern unfurling group

Cinnamon fern group

Cinnamon fern unfurling 1

Cinnamon fern

Christmas fern fiddlehead pair

Christmas fern

Royal fern unfurlng 1

Royal fern

Royal fern unfurlng

Royal fern

Bracken fern unfurling 1

Bracken fern

Bracken fern unfurling 2

Bracken fern

 

 

Swarming Season

The happiness of the bee and the dolphin is to exist. For man it is to know that and to wonder at it.

~Jacques Yves Cousteau

Just at closing one day this week, a coworker at the Garden sent an email alerting everyone to a swarm of honeybees just outside the back gate. I was getting ready for programs the next day so wasn’t able to get down there for an hour or so, but finally grabbed the camera and went out to see if I could find it. I asked a couple of people that were standing there talking if they knew the location of the swarm, but they had not seen it. About then, I saw some flying insects, and quickly found a ball of bees about 12 feet up on a small tree trunk.

Honeybee swarm

Honeybee swarm

I’m always amazed when I see one of these swarms…a buzzing blob that may contain hundreds to thousands of honeybees. Beneath all that is royalty, the queen. Swarms usually occur from late spring into early summer and appear more common after a mild winter and an early spring, like this year. A swarm is the process by which honeybees form a new colony. When the colony needs room to grow, the bees will raise a new queen. The old queen then leaves the hive with several thousand of her followers, leaving enough workers behind to take care of the new queen and the business of the old hive.

Honeybee swarm1

Scout bees are looking for a new hive location

The swarm usually flies a short distance away from the old hive and settles on some object (it can be a tree branch, a light pole, or even some part of a house). The queen is usually somewhere near the center of the cluster. Bees in a swarm are usually docile so there is no need to panic should you find yourself near one. The swarm stays in that temporary location anywhere from a few hours to a couple of days until scout bees locate a suitable new hive location, like a hollow tree or other protected spot. In the case of these bees, a local beekeeper was contacted and he came by the next day (unfortunately I had programs so did not get to witness this). He used a “bee vacuum” (a contraption that looks like a shop vac hooked to a box) to literally suck up the swarm so he could then relocate them to a backyard hive for honey production. Apparently, there is a network of beekeepers that can be called on for just this sort of service, which becomes even more valuable if bees decide to set up their new hive inside a dwelling or some other unwanted space.  In this case, both bees and human benefit from a sense of swarm on a late spring afternoon.

The Spirit of Spring

April hath put a spirit of youth in everything.

~William Shakespeare

Things have been so busy at work that I have failed miserably at getting outside with camera in hand to document some of the beauty around me. I made amends Saturday afternoon, and spent a few hours just wandering around the yard, observing and enjoying. I highly recommend it, especially this time of year. It is good for the spirit.

The species name means “spreading”, and, indeed, it does. There are large patches of this beautiful early bloomer in our shade garden.

One of my favorite spring wildflowers, wild geranium can vary quite a bit in the intensity of flower color. The ones in the yard are pale compared to those at work.

When viewed from above, a patch of mayapples looks like a crowd of ornate umbrellas. Kneel down and you see something quite different this time of year. If the plant has two leaves, it can produce a large white flower.

The common name comes from the small, apple-like fruit produced on fertile plants. These fruit are eaten by box turtles and mammals such as opossums, and the seeds dispersed in their droppings. Ripe fruits are edible, but all other parts of the plant are poisonous. Extracts from this species are being used to treat some forms of cancer.

 

This small creeping wildflower is easily overlooked, but is well worth the effort once you find it. I planted some in a soil-filled split in a log and it has now started to spread out on the ground around it.

Wild ginger

Hexastylis arifolia – Little brown jug (also called heartleaf, and wild ginger)

The distinctive heart-shaped leaves always give me pause to scrape away some leaves to see if I can find the flower that gives this widespread woodland plant one of its common names, little brown jug.

 

The flowers are believed to be pollinated by beetles, thrips, and small flies. Seeds are ant-dispersed.

 

This wildflower is quickly becoming one of my favorites. I bought a few plants from the NC Botanical Garden and the combination of unusual leaves and abundant flowers is a great addition to any woodland garden.

The airy nature of its abundant white flowers, coupled with long stamens, gives this beautiful wildflower its “foamy” appearance (and common name). I enjoy watching large bumblebees grab onto the column of small flowers and take a rapid dip toward the ground as their weight bends and bounces the stalk, providing some nectar, pollen, and a joy ride to the foraging bees.

The nodding yellow flowers of this plant have warty knobs on the inside of the petals. The protuberances may help bees get a better grip on the flowers as they climb in for nectar and pollen.

Sometimes, when you take the time to look around you, the familiar things take on a new beauty that helps you appreciate them. A pine cone among the wildflowers caught my eye and helped me appreciate the many patterns in nature.

Tree seedlings are a constant source of work in any woodland wildflower garden. If allowed to grow, they may quickly overtake and shade out many of the plants we hope to grow. But, I occasionally leave some as potential host plants for passing butterflies and moths. One tulip poplar sapling, growing at the corner of the house, managed to entice a passing female tiger swallowtail to pause and lay an egg. This egg seems to have an extra supply of whatever it is she uses to “glue” the egg to the leaf surface. Sometimes, less weeding pays off.

 

 

Spring Things

Now is the time of the illuminated woods… when every leaf glows like a tiny lamp.

~John Burroughs

Sharp-shinned hawk

Sharp-shinned hawk (click photos to enlarge)

Things happen so fast this time of year… it is the time of change. Old things moving on, new things appearing. Many of the birds of winter are heading north and are being replaced by bright and beautiful breeders from the tropics – the first ovenbird yesterday, the first Louisiana waterthrush earlier this week. The juncos disappeared over the weekend, but not before being terrorized by a sharp-shinned hawk one evening out back. There had been a rash of window strikes over the past two weeks, and now I think I know why. This fierce predator appeared late one day and chased a junco and tufted titmouse around and around a holly tree out near one of the bird feeders. The hawk had left some evidence (plucked feathers) that it was the probable cause of many of our yard birds leaving their wing imprints on windows in spite of the reflective stickers that adorn them. But this time, the birds eluded him.

Redbellied Water Snake

Red-bellied water snake (shot with iPhone)

At work, things not seen in many months have been exploding onto the scene. The resident water snake curled next to a path…

American toads in amplexus 1

American toads in amplexus (shot with iPhone)

American toads breeding in a small shallow pool already filled with many tiny black tadpoles from a previous amorous night…

American toads in amplexus

Laying eggs (shot with iPhone)

…leaving strands of eggs stretched across the mud.

Spring Peeper calling

Spring peeper calling

At home, the pleasing high-pitched calls of spring peepers each night. Things must be just right for them this week as the usually difficult-to-find songsters just keep calling, even when we approach them, flashlight and camera in hand.

Foamflower

Foamflower

And, while there are splashes of color appearing throughout the yard (columbine reds and yellows. the blue-purples of phlox), the white flowers dominate our spring woodlands.

Windflower

Windflower

Pinxter azalea

A pale pinxter azalea

 

Tulip poplar leaf unfurling 1

A tulip poplar leaf bursts forth

Soon, the dominant color will be green, the pale illuminated green of leaf out…my favorite woodland color. This is the week…get outside and enjoy the show.

Grass, Bottlebrush, Candelabra, Pine?

Here’s to the land of the longleaf pine,
The summer land where the sun doth shine,
Where the weak grow strong and the strong grow great,
Here’s to “Down Home,” the Old North State.

~North Carolina State Toast

In my last post, I talked about some of the amazing, small plants that grow beneath the longleaf, but not so much about the longleaf itself. It, too, is well-adapted for poor, sandy soils and thrives in an environment frequently visited by fire, and has some amazing strategies for surviving under those conditions.

longleaf savanna-29

Stand of longleaf in Croatan National Forest; the tall golden grasses are wiregrass which has seeded after a fire (click photos to enlarge).

Longleaf are not tolerant of shady conditions. In a mature savanna, they grow spaced fairly far apart so that each needle on each branch can receive as much sunlight as possible. They lose their lower limbs as they grow larger, and viewed from the ground seem to provide a loose, permeable canopy held aloft by elegantly arranged poles. This openness is one of the reasons that the savanna has such a diversity of low-growing species. The other is fire. Fire clears away other shrubs and trees, like turkey oak and gallberry, that typically grow beneath longleaf pine, and opens the forest floor for shorter species, like carnivorous plants, as well as seedling longleaf. Mature longleaf trees have thick bark that makes them resistant to all but the hottest fires. But with fire occurring every 3 years or so, historically, how would that allow new longleaf to sprout? Well, their growing stages are also perfectly adapted to this sandy, fire-prone habitat.

longleaf savanna-30

Recently burned longleaf stand in Croatan National Forest

A longleaf seed is most likely to be successful if it germinates in a relatively open area where it receives a lot of sunlight… which is just what you would find in a longleaf savanna just after a fire. The seedling develops into a special phase of life, unique to longleaf, called a grass stage. At this stage, the “tree” is just a tuft of needles at ground level that looks very much like the surrounding wiregrass. For a period of around 3 years (sometimes shorter, but sometimes much longer), the longleaf grows downward rather than upward, sending a taproot deep into the soil to fuel future growth. During this stage, it is, perhaps surprisingly, fairly fire resistant. The thick needles protect the all-important growing tip at the heart of the grass stage. Even if the needles are mostly burned, the tree can still make it!

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Grass stage longleaf trying to blend in with the surrounding wiregrass

When the time is right, the longleaf moves out of the grass stage with rapid vertical growth. It develops a thick, white bud-like tip, sometimes called a candle, and from there begins its growth.

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The growing tip or “candle” of a longleaf

Its goal during this time is to get tall enough and develop thick enough bark to survive a fire. This is no time to worry about branches, so the young tree looks much more like a bottlebrush than anything else; this stage is often called the “bottlebrush stage.” Though an educator on a workshop once suggested that it should be named the “truffula stage” after the crazy-looking multi-colored trees in Dr. Seuss’ The Lorax. During this phase the young longleaf is most susceptible to fire.

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Bottlebrush longleaf striving to grow as tall as its neighbors

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Bottlebrush longleaf after a fire – notice that it is still green around the growing tip!

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A group of young longleaf burned in a recent fire. Many still have green needles visible in the center.

But a tree just can’t grow up, and eventually the longleaf begins to grow out as well. The graceful side branches reach out horizontally and then turn up toward the sky. The “candelabra” stage is well-named! Longleaf tend to grow their 8-18″ long needles in clusters near the ends of branches, adding to the visual appeal of the tree.

At about 25-30 years, longleaf reach maturity and start producing cones. Though the species is fire-adapted, it does not have serotinous cones – cones that open in the heat of fire. A neighbor to the longleaf, the pond pine, which commonly grows in boggy pocosins adjacent to longleaf savanna, does have serotinous cones. My coworker Megan decided we needed to observe this phenomena for ourselves; so, armed with a lighter and a closed pond pine cone, we did! With the heat from the lighter, the scales of the cone opened with an audible pop, kind of like the popping of popcorn. Inside each scale were two winged seeds, as with other pines. Pond pines also grow best after fire, so their serontinous cones are a great adaptation to promote growth when the conditions are right. Longleaf don’t use that strategy even though they depend on similar conditions for germination. But their cones are equally impressive. The largest pine cones in North Carolina, they can be up to about 12″ long!

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Pond pine cone, opened after a fire

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Longleaf cone with my size 9 (men’s 7) rubber boot for scale

The oldest documented longleaf in North Carolina is found in Weymouth Woods State Park and is more than 465 years old! Though perhaps at one time there were many such old monarchs of the forest, that’s rare now. But mature longleaf play a very important role in the ecosystem, particularly for red-cockaded woodpeckers. As longleaf age, they become more susceptible to red heart fungus, which softens the (very hard) heartwood of the tree. Red-cockaded woodpeckers are our only species of woodpecker that seek out live trees for nesting, and they prefer mature longleaf pine that are infected with red heart fungus. This is because they hollow out nest cavities in the living trees, and the softening due to red heart makes that easier. They also peck holes in the tree surrounding their cavity that draw out the tree’s sticky resin. This acts as a defense against a common predator, rat snakes. If you’re visiting a longleaf forest and spot trees painted with white rings, look up for the cavity! Biologists studying RCWs mark their nest trees in this way to make them more visible.

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RCW cavity – this one doesn’t have extensive resin wells drilled around it.

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The distinctive white band of an RCW cavity tree. I like to joke about the endangered woodpeckers who fly around with a paintbrush in their little feet to mark their homes so they can fine them again later…

The longleaf pine savanna is an amazing diverse habitat, and the longleaf pine is well-adapted to live there. If you have the chance to visit, see if you can spot each stage of its life – grass, bottlebrush, candelabra, and mature tree!

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Graceful, mature longleaf

The Most Wonderful Plant in the World

“This plant, commonly called Venus’ fly-trap, from the rapidity and force of its movements, is one of the most wonderful in the world” and “is one of the most beautifully adapted plants in the vegetable kingdom.”

~Charles Darwin

One of the tree species Mike didn’t include on his recent tree bark quiz, probably because it’s much less common in our area than the loblolly pine, is the longleaf pine. It has the thickest and most resinous bark of any of our pines, the longest needles, and the largest cones. But perhaps most interestingly, at least to me, is the ecosystem that grows up around it.

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Longleaf savanna in the Green Swamp Preserve

Longleaf forests once covered up to 60 million acres in the southeastern US, stretching from southern Virginia to eastern Texas. Early explorers and colonists saw dollar signs when they gazed upon the ‘endless’ forest: a source for all sorts of exportable products. The first major economic driver in North Carolina was the naval stores industry – the production of lumber, tar, pitch, and turpentine. Longleaf grow straight and true, making fantastic masts. Their resinous heartwood, called fatwood or lighterwood, was slowly burned under piles of earth, releasing pungent tar. Tar was boiled to thicken it into nearly-solid pitch. Tar and pitch were essential to the sea-worthiness of wooden ships: ropes and sails were soaked in tar, seams in the hull (and pretty much all other wood on a ship) were coated in pitch. The bark of living trees was scraped away, releasing the tree’s natural defense, resin, which was collected and distilled into turpentine. Turpentine had numerous uses, including as a remedy for colds (probably not the best idea). Though the longleaf forest must at first have seemed vast and limitless, after a century or more of harvesting, the once extensive blanket of longleaf pine in the southeast was reduced to about 3% of its original range.

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Cat-faced tree in Croatan National Forest; longleaf trees were cut in a distinctive “cat face” pattern to promote the production and allow the collection of resin for distilling into turpentine and rosin.

I’ve never been a huge fan of pines. When I lived in Durham, my house was surrounded by huge loblollies, and the yard was ALWAYS covered in pine needles. But a trip to a longleaf pine savanna can change that perspective fairly quickly. Longleaf are so successful in their habitats that they form what at first seems to be almost a monoculture – longleaf, and only longleaf, growing rank on rank as far as the eye can see. They are straight trunked with a waving crown – their lower branches drop off as the tree grows. But if you look a little closer at the dense ground cover, you’ll soon find that the longleaf pine forest is a surprisingly diverse ecosystem.

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Row upon row of longleaf, with a live oak standing out in the foreground. The oak is growing in a slightly wetter area at the edge of an ephemeral pool.

Some surveys of the ground cover in longleaf savannas have revealed more than 50 species of plants within one square meter. That is more diverse than a rainforest, at a small scale! And in North (and South) Carolina, we have some amazing species that live in that niche. Because of the nutrient poor soils found in longleaf habitats, plants need to have a good strategy for gathering the nutrients they need to thrive. Carnivorous plants have adapted some amazing ways to get nutrients from the ubiquitous insects that also live in this ecosystem. There are 4 primary groups of carnivorous plants in the savanna: sundews, butterworts, pitcher plants, and the most famous of all, the Venus fly trap.

When I saw my first fly trap, I must admit that I was a little disappointed. My high school put on “Little Shop of Horrors” when I was a student there, and Audrey was a pretty impressive, man-eating fly trap. In contrast, the traps of the real plants only get to be about 1 inch in diameter. But if you get down close to them and watch them in action, they are still impressive! The traps are actually modified leaves. They have green or red centers, the mid-rib of the leaf, each with 2-3 “trigger hairs” on the inside of the trap. The traps secrete sweet sap to lure their prey in and are rimmed with thin spines that will prevent escape. The spines look quite vicious, but are in fact more hair-like and won’t hurt you at all if you touch them. When an insect (or a pine needle yielded by a curious observer) touches two trigger hairs in quick succession, the leaf closes, trapping the insect. The repetition is important because the fly trap doesn’t want to be confused and close during every rainstorm! I hadn’t “tickled” a fly trap in a while, so on a recent trip to the savanna, I decided to try it out. Though I’ve done this before, I had forgotten just how quickly the leaf can close! Within less than 1 second it was shut. Apparently, this is one of the most rapid movements in the plant kingdom. Fly traps will reopen after a false trigger like mine, but it may take as much as a day for them to do that. And, they will only close so many times before turning black and dying, so it’s important not to “tickle” fly traps too often. But we typically encourage groups of teachers to try it, as it is an unparalleled educational opportunity to observe this amazing plant species. I filmed this video of a flytrap closing on a recent teacher workshop visit to a longleaf savanna.

Click here to see a video I took in the Green Swamp of a Venus fly trap closing!

Venus fly traps only grow within about a 100-mile radius of Wilmington, NC. Like longleaf, they depend on fire to keep their growing areas clear of taller species that will shade them out (more on fire later). They thrive in ecotones (areas of transition from one plant community to another) at the border between longleaf savanna and pocosins (shrubby bogs of the coastal plain). Because they are so interesting, and so rare, poaching has become a problem for fly traps. About two years ago, North Carolina increased the stakes for fly trap poachers – it is now a felony in NC.

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Venus Fly Trap

But fly traps aren’t the only show in town. Other types of carnivorous plants also thrive at the edges of the pine savanna, including pitcher plants, sundews, butterworts, and bladderworts. The insect-trapping strategy for each of these is different. Pitcher plants lure insects inside and then trap them in their tubular leaves which are slippery and lined with downward-pointing hairs. The insects can’t escape and the plant exudes digestive juices to claim its nutrients. Purples pitcher plants, Sarracenia purpurea, are a little different – they drown their prey in pools of water.

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The open leaves of the purple pitcher plant fill with water and drown insects… but inside of this one there was a small mosquito larva swimming around!

But even a pitcher plant can’t eat everything that falls in. Frogs sometimes hide out in them, a few species of caterpillar feed on the inner surface of the pitcher, and there’s even a species of wasp that lays its eggs in the shelter of the pitcher. Sundews look a bit like pin cushions that were left out overnight and have been coated by dew. The sweet-smelling droplets are both the lure for prey and the reason for its demise. It is entrapped in the sticky substance, and the leaf rolls up around it. The same sticky secretions also contain enzymes that digest the insect, providing the nutrients the plant is not getting from its environment.

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Notice the vivid, red sundews and the sandy soil in which they’re growing.

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We have 5 species of sundew in NC, 4 of which occur in eastern NC (the other prefers mountain bogs and a few sites in the Sandhills). I think this species is Drosera capillaris, but I’m not entirely sure without seeing a flower or seed.

Butterworts are a startling yellow-green color that stands out from the golds and browns of surrounding species in late winter/early spring. Their strategy for capturing prey is similar to sundews. They secrete a sticky substance on the surface of the leaf that lures, traps, ensnares, and digests small insects.

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There are 3 species of butterwort reported in NC. According to Radford’s maps of their ranges, I think this is Pinguicula caerulea.

The final group of carnivorous plants found in this type of habitat are bladderworts. Bladderworts are the most varied (species-wise) of our carnivorous plants – there are 14 or 15 species in NC! The bladderworts I have seen in the past are aquatic. Their underwater roots have bladders that suck prey in to be digested. Apparently, there are also terrestrial bladderworts that live in boggy peat soils or moist sand. I didn’t realize this before my trip, so I’ll have to search them out when I return!

Though fly traps have the most limited range of our carnivorous plants, each type is remarkable in its own way and well-worth seeking out in some of the remaining longleaf pine savannas. They’re easy to miss when not in flower, but if you scour the edges where pocosin meets savanna, you might be fortunate enough to find some!

Party Surprise

I put 100 hickory nuts on my bureau at dusk one fall evening…by midnight, she had stored them all. At midnight…counted another 100 hickory nuts and spread them. The next morning, every nut was gone. She had picked up and stored 200 in one night.

~John Terres, on how many nuts his captive flying squirrel could store in one night

We had a gathering of friends at the house this past weekend, complete with campfires, and basic outdoor foods like hot dogs, beans, and coleslaw (did I mention S’mores?). It was a beautiful, crisp evening and good conversations and laughter were heard in our woods for several hours. Natural history highlights included seeing a couple of spotted salamanders laying eggs in one of our pools, and listening to the resident screech owl wailing across the ravine. But, the event that drew the biggest gasps and sounds of joy was a surprise sighting I had out back after several guests had already called it a night. I took some bottles and cans out onto the back deck where we had put our recycle bins and the bottles clanked loudly as I dropped them in. A few feet away, some people were laughing just inside the screened porch. I turned to join them, when something caught my eye…

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Southern flying squirrel in my bird feeder (click photos to enlarge)

I noticed a shape sitting in the bird feeder that hangs suspended between the house and a nearby tree. A bird this time of night???…nope, a flying squirrel! I have seen and heard them (they make high-pitched chirps that sound like birds at night) in these woods before, but never seen one on the feeder (probably because I rarely turn on the lights on the deck). This little guy didn’t seem to care that I was only a few feet away staring at him. I whispered to the folks on the porch and they came out…the noise level increased, but still no sign of stress. I went out to the campfire circle and told folks about my find, and soon there were close to a dozen people gathered on the deck excitedly watching this beautiful little creature.

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Close up of flying squirrel

In spite of the increased noise, and a flashlight beam shining on it, the squirrel continued to chow down on sunflower seeds and glance back at us with those large dark eyes. Of course, those big eyes are an adaptation for their nocturnal lifestyle. Combined with a keen sense of hearing, flying squirrels use their oversized eyes to help find their way in the darkness and avoid dangers like owls and terrestrial mammals. I was surprised to read that these abundant little squirrels actually spend a fair amount of time foraging on the ground at night, where they are much more vulnerable to predators.

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The fold of skin that allows a flying squirrel to glide

As you probably know, flying squirrels don’t really fly, they glide. The special adaptation that gives them this unique ability is a fold of furred skin (patagia,; singular patagium) that stretches on either side from the wrist to the ankle. The photo above shows the edge of one of these folds. When a flying squirrel leaps off of a tree, it stretches its legs wide, and the the patagia form a wing-like structure that enables the squirrel to glide downward. Using small movements of the feet and tail, they have remarkable skill in directing their glides and can make sharp turns and precisely hit targets (like a suspended bird feeder). Though usually from tree to neighboring tree, their glides can cover much larger distances (well over 100 feet).

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Flying squirrels have wide, flattened tails

Another useful body trait for a gliding mammal is a long (about half their total body length) flattened tail that can act as a rudder in flight. Right before landing on a tree trunk, flying squirrels assume a vertical position, legs spread and tail down, which helps serve as a brake in their glide.

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Hickory nuts in flying squirrel “nest”

So where are they going with this special talent? Usually in search of food (or to escape predators). Flying squirrels are omnivores, eating a wide range of vegetable and animal materials. They are especially fond of nuts and seeds, but will also dine on insects and birds eggs and young. Most people don’t realize how common our flying squirrels are, even in urban settings (they are often as common as the more noticeable Eastern gray squirrels). A sure-fire clue is the presence of nuts that have a hole chewed in them like the ones pictured above. A recent visitor to the Garden brought in this “nest” from a bluebird box in her yard that she had cleaned out. The nest contained four hickory nuts and she wondered what was using the box. Flying squirrels use tree cavities, nest boxes, attics, and my storage shed, among other places, as nesting spots and retreats. This nest was lined with shredded cedar bark (a favorite of flying squirrels) and contained the tell-tale evidence of nuts with a hole chewed in them.

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A Southern flying squirrel, one of our cutest mammals

We have two species of flying squirrels here in North Carolina – northern and southern. The latter is what we have here in the Piedmont and throughout much of the region. Northern flying squirrels are slightly larger and are restricted to higher elevations in our mountains and habitats further north. Our party squirrel finally decided it had had enough of the gawkers, and nimbly darted up onto the wire and glided over to the nearby oak tree, dashing around to the side of the trunk when it landed. It paused there and stared at the crowd before retiring into the darkness, giving us all a fantastic look at one of our most endearing mammals and a lasting memory of a gathering in the woods.