Thursday, January 8, 2015

Action plants!

Longleaf pine savannah, Louisiana
It is an interesting time to love rare and unusual plants. Just a few months ago, a man in Boone, NC became the first to be charged with a felony for poaching the rare (and highly lucrative) ginseng. Dried ginseng is worth four times its weight in silver. Most growers keep their operations secret because poaching, not the vagaries of weather, pests, or animals, is the biggest threat to their livelihoods.

A venus flytrap in situ at the Green Swamp
Again in North Carolina, a few days ago four men were the first to be charged with felonies for poaching venus flytraps. Unbelievably, before the law was changed December 1st of last year, the maximum penalty was a misdemeanor and a $50 fine. $50 seems down right paltry when you consider that venus flytraps are only found on poor soils in the longleaf pine savannah on the coastal plain of North and South Carolina. The Nature Conservancy estimates that there are fewer than 35,000 venus flytraps remaining in the wild.

I have lived most of my life in the southeastern United States, and I have had the privilege of seeing many different types of carnivorous plant in the wild in North Carolina, Alabama, and Louisiana. Plants develop carnivory as a means to get more nutrients on poor soils. Simply put, this strategy doesn't pay on better ground. Snap traps, sticky trap, or pitcher, these plants all must expend energy to build these contraptions. While flytraps are rather limited in distribution, sundews and pitcher plants can be found along much of the Atlantic coast and in the Great Lake states.

A sundew (no, that isn't my hand and no, I didn't pick it)
classic pitcher plant
I have seen venus flytraps, sundews, and pitcher plants. These three families, along with bladderworts, make up some of the major clusters in carnivorous plant taxonomy.  Sundews and flytraps are actually somewhat related. Flytraps seem to have evolved from a sundew-like ancestor.

Sundews capture their prey with a sticky trap mechanism- what looks like dew is actually an adhesive. Once an insect is caught it will not be released. The venus flytrap, cousin to the sundew, is instead reminiscent of a steel trap. Once an insect brushes its trigger hairs, the jaws snap shut and imprison it.

Pitcher plants are less closely related, and their traps are much more passive. An insect falls in and is slowly dissolved in an enzyme bath at the bottom of the pitcher. Should it try to climb out, downward facing hairs trip it up and hinder its escape.

Another type of pitcher plant. Notice the hair.
Texas has one species of pitcher plant (Sarracenia alata) and up to four species of sundew (Drosera brevifolia, D. capillaris, D. intermedia, and D. tracyi).  I haven't yet found these plants, but the BONAP maps show them pretty far inland. Sundews are unobtrusive and hard to spot, but pitcher plants might be worth an expedition. Especially during their summer bloom.

A blooming pitcher plant

Longleaf pine savannah, North Carolina


  1. The woods around Gautier, where my paternal grandparents lived, had poor soil, sundews and pitcher plants.

    1. Gautier, MS, on the west bank of the Pascagoula River, near the Mississippi Sound.

  2. I still would like to understand the mechanism that determines the spacing of those trees.

    You forgot to mention one of my favorite carnivorous plants. You forgot the Pinguiculas.

    I have had a venus flytrap for a number of years. Each year I plant it in a small bog garden I have in a pot outside. I then dig it up and bring it back inside in the fall so it can survive my areas cold winter. The neighborhood kids love to feed this flytrap. The bog garden is really for my orchids, but the venus flytrap is a nice addition.

    1. How cool James! I did not know about those plants. You must be a skilled gardener- I've killed every orchid I've brought home.

      RE: tree spacing: longleaf pines have massive tap roots. I would bet their rooting systems, combined with regular fire, contribute to the openness of the pine savannas.

    2. I like the Mexican Pinguiculas because they have showy flowers and make good terrarium plants. I have 10 species and hybrids in a 55 gallon terrarium with grow lights in front of a South facing window. Another bonus of Pinguiculas is they can tolerate an amount of lime and shade which would kill other carnivorous plants.

      Growing orchids is not as hard as people have made it seem. I think most people make the mistake of use tap water. Tap water has too many minerals. I collect rain water and give this to my indoor and outdoor orchids with a little fertilizer added for the indoor orchids. I also put my indoor orchids under a tree for the summer. They seem to enjoy being out of the dry air in the house.

      The orchids I grow outside in bog garden pots are Calopogon tuberosa varieties and Habenaria radiata. I simply take an undrained pot, fill it with sphagnum peat, and then dress the top of the pot with long leaf sphagnum peat moss. These pots only receive rain water. I collect any bog water that drains out of these pots and use it to water later when the water level in the pots has dropped. Collecting water from the pots is accomplished with some aquarium tubing and an old milk jug. The Calopogons double about every year and a half. Consequently, my pots have quickly become full of this little orchid. I dig them up each fall and store them in the refrigerator to protect them from the cold. I have to weed out the sedges that grow, but the Rynchosporas do not seem to compete too much with the orchids.

  3. I know a few locations where you can see the carnivorous plants especially the sundews and pitcher plants.