S. rosea vs. clarified S. purpurea

I'll be updating this message, but for for now, I am creating this thread to highlight the differences between two species of Sarracenia, S. purpurea (the purple pitchers plant) and S. rosea (Louis Burke's pitcher plant). From what I can tell, most of the confusion about these two species has been caused by their historical treatments. There are many publications which refer to the range of S. purpurea venosa as extending south along the coast of Georgia, down into the Florida panhandle and west into Alabama, Louisiana and Mississippi. However, none of these statements regarding the shape of this range have been backed up by evidence.

The situation in Georgia doesn't seem to represent an extension of the range of S. purpurea venosa south, but instead the southern limit of its range. Areas south and west of the north eastern corner of Georgia yield no purple pitcher plants; and there are no historical records of them ever having occurred south or west of there. This means we should not assume there is a direct connection between the ranges of S. purpurea and S. rosea, as it has been portrayed in many publications. They are separated by close to 200 miles and there is no evidence the situation now is any different from 10,000 years ago.

There actually seems to be three subspecies of S. purpurea, the one called S. purpurea venosa range is from north eastern Georgia up into Virginia, perhaps as far north as New Jersey or even Long Island.

This is where S. purpurea purpurea range starts, but this subspecies is confusing, there seem to different plants along the shore, different plants in the mountains, and even an other kind around the Great Lakes. One subspecies found along the coast from Delaware up through Massachusetts.

The other is more inland and is found in the mountains and west into the Great Lakes region. All the of populations which also have form S. p. p. heterophylla are part of this third, unnamed subspecies (or currently lumped into subsp. purpurea). This is the same kind of purple pitcher plant which have the vein-less and bronze forms which have been recently discovered by Jay Lechtman and Carl Mazur.

The three main kinds of purple pitcher plant are all very close to each other, resembling each other at different times of the year. The flowers on all three types are very similar in their coloration, shape and odor. However, S. purpurea venosa burkii or S. rosea maintains a different appearance all year long. The flowers are different from the other purp groups, indicating the plants from the Gulf Coast area have been on a separate evolutionary path for quite a while, longer than the northern subspecies, which are all closer to each other even though the combined ranges of S. purpurea purpurea and venosa are much larger than the range of S. rosea.

Bye for now,
Dave E.
www.dangerousplants.com