HAMMONTON — Russell Juelg reached his hand into a pond off Route 206 and pulled out an unremarkable string of vegetation that also is a complex, bizarre plant few people know about.
Living throughout southern New Jersey are more than a dozen varieties of a carnivorous, aquatic plant called bladderwort, a favorite of Charles Darwin's that still intrigues scientists today, even though most people either never notice it or think of it as a water-dwelling weed.
"It's not the most charismatic plant," said Juelg, a botanist and director of outreach for the Pinelands Preservation Alliance, "but when you look at it real close, it's fascinating."
Plants that eat other organisms, such as the sundew, pitcher plant and Venus fly trap, often are featured in big-production nature programs such as the Discovery Channel's "Life."
More than 200 bladderwort species live in placid pools of water and saturated muck on every continent except Antarctica. The plant catches prey in tiny, balloon-like bladders that either dangle in the water or sink into the mud. When organisms brush against tiny hairs at the bladder's entrance, the trap opens and forms a vacuum to suck in the food, digesting it and expelling the water to make room for more.
"Apparently, people have been stumped by this plant for a long time because its system is so unusual," Juelg said.
The obscurity of bladderworts in New Jersey may be due to the plants consuming mostly small and unexciting things, such as tiny planktonic crustaceans, although some varieties eat mosquito larvae and tadpoles.
Nine of the region's 15 bladderwort species are rare, three are endangered and the rest are of special concern.
This spring, Juelg set out to improve at identifying bladderwort species. On a recent Thursday morning along the northwestern border of Atlantic County, it seemed he still needed some work.
"Now, what is this?" he said, staring at a bladderwort stem he pulled from a puddle in an overgrown dirt road leading into the Pinelands, before sitting on a muddy lump and leafing through his field manual.
Flowers give it away
The easiest way to find and identify the plant is when it is flowering, which it does from early June through August, depending on the species. The typically yellow and white flowers, although small, are prized by some enthusiasts, and are compared with orchids and snapdragons.
Without the different flowers sticking up like skinny flags out of the water or mud, the tentacle-looking leaves with their seed-sized bladders are all plant scientists have to examine.
"It's a very minute plant," said David Snyder, the state botanist with the Department of Environmental Protection's Division of Parks and Forestry. "You can't even find it when you're looking for it," which is why the plant is considered the ugly duckling of the state's three native carnivorous plants.
Pitcher plants are common along the state's waterways. They can be grown in pots at home, where they can be hand-fed insects.
Sundews use sticky traps and tentacles to snare unsuspecting flies.
The disparity among the state's carnivorous plants was obvious as Juelg traipsed through the dried-out trails near Atsion Lake. He could easily point out the red, shining sundews scattered along the trail, while the bladderworts looked like veiny webbing in the cracked mud.
A Vineland botanist named Mary Treat corresponded with Darwin on bladderworts and helped him with the research for his book "Insectivorous Plants."
Before her death in 1923, Treat examined the plant's trapping mechanism, watching it as it sucked in prey that floated by and dissolved its food in its transparent stomachs.
Darwin in turn gave the plant special treatment in his book, and discussed it often with fellow researchers.
"What a wonderful and long-continued series of variations must have led up to the perfect ‘trap' in Utricularia (the bladderwort's genus)," fellow evolutionary theorist Alfred Russel Wallace wrote in a letter to Darwin in 1875, "while at any stage of the process the same end might have been gained by a little development of roots and leaves, as in 9,999 plants out of 10,000!"
Bladderworts do indeed lack roots. Many varieties sit in the mud, and their bladders catch small creatures crawling underneath, while others float freely in the water and hang their leaves below the surface.
Carnivorous plants are fond of nutrient-poor areas, because they get their sustenance from their prey and not the soil, hence their residence in the pinelands.
"Since the Pine Barrens are very poor in nutrients, and acidic to boot, the bladders, sundews and pitchers do especially well there," said Peter Straub, an associate professor of biology at The Richard Stockton College of New Jersey.
Location could be another reason they are not exactly a plant-fan favorite.
"They commonly inhabit, as more than one observer has remarked to me, remarkably foul ditches," Darwin wrote in "Insectivorous Plants."
But Straub said that because bladderworts are mainly aquatic, they are particularly affected by fertilizer runoff and urbanization.
That should be a concern, Juelg said, because the plants are not only an important part of the ecosystem's food chain, but they provide habitat for other species as well, such as shelter for marine animals below them.
Just before noon by Atsion Lake, Juelg left the trail and made his way through the underbrush to a waterless but soggy creek.
Several bright yellow flowers plunged out of the muck, and Juelg immediately knew what he was dealing with from the shape of the flowers and the way the bladders were aligned on the leaves sprawled across the mud.
"This is Utricularia geminiscapa," he said of the hiddenfruit bladderwort, a variety that is found principally in northeast North America but also grows in New Zealand.
The plant was the third species of bladderwort he identified that morning. On the way back to his Jeep, stepping over sundews, he rewarded himself with some wild blueberries.
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