Assabet River NWR Final CCP - U.S. Fish and Wildlife Service

Chapter 3: Refuge and Resource Descriptions
A total of 8 rare plant species were documented on the property, including
a state-listed endangered species (se), a state threatened species (st), two
species listed by the state as being of special concern (sc), and three state
watch list (wl) species and are shown in Table 3-3. Special concern species,
a lady’s tresses (Spiranthes vernalis) listed in the Aneptek report as
occurring on the property, was not found by Hunt. Hunt found the more
common lady tresses (S. cernua) within the same location as the Aneptek
record, and believed the earlier identification may have been incorrect.
Included in the species found by Hunt were an additional 34 species (26
native and 6 introduced), which he characterized as being uncommon in
eastern Massachusetts.
Table 3-3: Rare Plant Species at Assabet River NWR
Common name Scientific name Status 1
Midland Sedge Carex mesochorea SE
Few Fruited Sedge Carex oligosperma ST
New England Blazing Star Liatris borealis SC
Philadelphia Panic Grass Panicum philadelphicum SC
var. philidelphicum
Small Beggar-Ticks Bidens discoidea WL
Lacegrass Eragrostis capillaries WL
Northern Starwort Stellaria clycantha WL
1 SE – state-listed endangered, ST – state-listed threatened, SC – statelisted
species of special concern, WL – state watch list
Vernal pools
Vernal pools are a priority habitat type within the state of Massachusetts.
Several vernal pools have been identified on the Assabet River NWR
(Dineen 2001). Additional surveys to locate vernal pools were initiated in
the spring of 2001. Vernal pools are temporary freshwater depressions
which hold spring rains and snowmelt waters, and then typically dry
out during late summer. Vernal pools are critical breeding habitat for
amphibian and invertebrate species due to the lack of predatory fish.
The vernal pools of Assabet River NWR are confirmed breeding
habitat for the blue-spotted salamander (Ambystoma laterale), which is
a state species of special concern, and spotted turtles (Clemmys
Vernal Pool: Photo by Rob Vincent
guttata), have also been observed on the refuge (Meyer and
Montemerlo, 1995).
Invasive or Overabundant Species
Hunt found that the number of exotic plant species was lower than
expected, in part due to the undisturbed nature of the former Sudbury
Training Annex. However, Hunt identified 19 species on the property that
are included in a listing of “nonnative, invasive and potentially invasive
plants in New England” prepared by Dr. Leslie J. Mehrhoff of the
University of Connecticut (UCONN 2000). No surveys have been
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