Ecological and Bacteriological Notes on Pitcher Plants
and Certain Other Carnivorous Plants

by John A. Lindquist

Most of the material in these pages is based on my old (1975) M.S. thesis: Bacteriological and ecological observations on the northern pitcher plant, Sarracenia purpurea. Department of Bacteriology, University of Wisconsin, Madison, WI.

As of 1975, the carnivorous plants known as pitcher plants had been studied very little regarding their digestive activities and microbial associates. Some researchers considered the participation of bacteria in the foliar digestion of insects, but no isolations or identifications were made. My thesis research was undertaken to investigate, by enrichments, platings and isolations, various microbial groups within the pitcher leaf of Sarracenia purpurea, including those possibly active in the digestion of insects. The study was expanded to include observations on the plant and its habitat such as growth patterns of the leaves, insect associates and characterizations of the habitat as to nutrient availability.

Relevant items appearing on these web pages:

I am always interested in taxonomic updates on Sarracenia and results of any research on the digestive processes concerning S. purpurea. The following have been burning questions over the years, and some of these items are addressed in the book by Dr. Schnell mentioned below:

  • Is there really any involvement of plant-produced degradative enzymes in S. purpurea or other pitcher plants?
  • What is the actual function (if any) of the so-called (by some) "digestive glands" of S. purpurea?
  • Do bromeliads reap any benefit from the activities of bacteria degrading insects in the water they collect (absorption of ammonia, for instance)?

Questions you may have about carnivorous plants (species, types, cultivation, habitats, biochemistry, etc.) may be answered by searching the web, starting with The International Carnivorous Plant Society Site where you can also get information about the Carnivorous Plant Newsletter. Carnivorous Plants of the United States and Canada by Dr. Donald E. Schnell is an excellent resource.

DISCLAIMER:  You can e-mail me (address given on my home page) and I can answer questions about specific items on the photo and bacteriological pages, but I am no general expert on the subject of carnivorous plants! I have had no experience with Nepenthes or Darlingtonia. Also, I cannot advise on obtaining or cultivating carnivorous plants. These are activities for which I have not had the time, interest or facilities, as I prefer to visit these plants out in their habitat. Questions about collection and conservation are entirely out of my league. The Natural Resources departments of the various state governments can help with those matters, and the links above refer to expert information.

The mullein page
features the great
mullein in 3-D.

Page last modified on 11/10/08 at 10:30 AM, CST.
John Lindquist, Department of Bacteriology,
University of Wisconsin – Madison