This is the only Horsetail species in New England that commonly has compound branches coming off the stem. In other words, branches coming off the main stem split up into smaller branches. Some of the other key distinguishing features are:
- Whorls of branches coming off the main stem.
- Length of the first internode of the branch is equal to or longer than the sheath on the stem immediately above the branches. (Click on the first picture in the second row of pictures to the right.)
- The leaves at the end of each sheath on the main stem are brown or read and are joined into 3 to 4 groups.
- Diameter of the stem cavity is 50% or more than the diameter of the whole stem.
