Mary Treat – Female Naturalist of the Pine Barrens

Celebrate International Women’s Day with this blog about Mary Treat and her important contributions to the understanding of the ecology of our most fascinating carnivorous plants.



Mary Treat (Mary Lua Adelia Davis) was born in 1830 in New York and moved to Vineland, NJ which was known as a progressive intellectual agrarian community. Mary, an American botanist and entomologist, and her husband moved there to start a fruit farm and to study insects that were injurious to crops. They separated in 1874. Mary was able to support herself with her writing talent and became a popular nature writer and prolific naturalist of the Pine Barrens. Her discoveries included a new species of orange aphid, ichneumon fly, two spiders, and an ant that was named in her honor: Aphanogsten Treatiae. 

Her research and observations of Utricularia, better known as Bladderwort, earned her the respect of the world’s most famous naturalist, Charles Darwin. They corresponded for five years between 1871 and 1876 as she shared her observations, experiments, and samples of native carnivorous plants of the Pine Barrens. Her first correspondence with Darwin in December of 1871 describes the fly-catching mechanisms of Drosera, or Sundews, a fascinating carnivorous plant of the wetland area of the pines.  

The following is from a letter from Charles Darwin dated July 1, 1875, regarding the function and mechanics of the specialized bladderlike structures of the bladderworts (from “Home Studies in Nature” by Mary Treat, Copyright 1885 Harper Brothers). Darwin believed that mosquito larvae entered the structures by using their head as a wedge. This was contrary to Mary’s observations, where the plant structure actively reacted and sucked the aquatic creature into the structure where it would be digested and absorbed. At times the deceased mosquito larvae’s head would protrude from the opening making it highly unlikely that they forced their way in.  

Image of bladderwort captured by Monica Cahill

“ I have read your article with the greatest interest. It certainly appears from your excellent observations that the valve was sensitive, and I hope it may be so from homologizing with pinguicula; but I cannot understand why I could never, with all my pains, excite any movement. It is pretty clear I am quite wrong about the head acting like a wedge. The in draught of the living larva is astonishing.” 

Mary’s writing career spanned 50 years with popular science scientific articles published in Harper, Magazine, American Naturalist, Journal of American Entomological Society and Lippincott’s Monthly, New York Tribune, and Atlantic Monthly. She also published 5 books including the aforementioned Home Studies in Nature and her book, Injurious Insects of the Farm and Field (1882), was reprinted five times. 

Mary lived to be 92 years old and spent her last years with her sister in New York State where she passed away on April 11, 1923. She was laid to rest in Vineland, NJ where she lived and studied for many years. 

As you paddle or hike in the Pine Barrens, remember Mary Treat and her important contributions to the understanding of the ecology of our most fascinating carnivorous plants.

If you would like to learn more about Mary Treat you can read, Mary Treat: A Biography by Deborah Boerner Ein.