Tuesday, July 4, 2017

Parasitic Plants

Orobanche uniflora

I have been told that Massachusetts is the home of four Parasitic Plants. In my years of hunting and photographing wild flowers I have only found three of the four species. Above is one of my rarer finds, though I believe it is fairly common, One Flowered Broom Rape, or One Flowered Cancer Root, as my older flower books called it. These plants have specialized roots to feed off of its host plants and no chlorophyll at all. Host plants for it are sedums, saxifrages, sunflowers, goldenrods and others.  I have found this species in open sunny locations, but only in the spring (May).  The difficulty is that it may bloom one year in a location then not again the next year, these are annual plants.

The thing to remember is that all of these representatives are true flowing plants, they are not mushrooms or other fungus.  Those don't just look like flowers they are flowers and the plant will set seed after a pollinator comes to visit. The one thing they all have in common is they lack chlorophyll so they cannot produce their own nutrients from the sun and must acquire them from other sources.              


Monotropa uniflora

A second and much more common parasitic plant is Indian Pipe. I am sure that most of us who spend any time walking in woods have seen these ghostly stalks poking their heads up in the forest floor.  Since their main host is pine trees they are often seen growing through a bed of pine needles. Unlike my other two parasitic plants Indian Pipes don't use specialized roots to attach to their hosts roots instead they take advantage of a soil fungus which is itself feeding off of the pines.  

These newly emerged plants above all have their flower heads pointing down. This keeps the rain water out of the flower. As the plants mature the flower heads will tilt more horizontally then vertically.


The above photo shows the flower heads in various positions. Once pollinated the flower head will move to a vertical position.  I once saw a bumblebee crawl out of the flower of an Indian pipe, started me so I didn't get a photograph, but it also reminded me that these are not mushrooms.


The old plants turn brown or black. You can see that happening in the above group photo, note that most of the flower heads with their developing seed pods have turned up. You can find these plants in pine woods throughout the summer if there has been enough rain to support their growth, the plants don't survive very long, a few weeks or so.

Conopholis Americana
My third Parasitic Plant is Squaw Root, and it uses specialized roots to feed off of Oak Trees. I have only found this plant in one location, though a couple of years apart. The photo above shows it in bloom.


Here you see it in a later stage where the seeds are developing. The above photo actually represents the first time I found the plant, while the first photo is the 2nd time.  The plants bloom in May (in MA) but develop over a month or two, my second photo was made in June. According to what I have read the plants can linger through winter though they will turn brown. 

As I mentioned above I have heard that there is one other Parasitic Plant to be found in MA., however I cannot find an official list of Parasitic Plants in MA so I am unable to find a name. I believe it is a multi bloom version of Bloom Rape (there is a plant like that in VT. it is not native and hasn't been found in MA as far as I know.). If any reader has further information please feel free to share it with me.

That is it for today. Hope you enjoyed seeing and reading about our Parasitic Plants.