Plant Survey at Six Ponds, Plymouth
A.Zinovjev and I.Kadis
August/September 2015

The total number of plants recorded is 306, of which 243 are native (including 7 of conservation concern) and 63 introduced (including 23 invasive). The results are only preliminary due to short survey time. Additional surveys during other seasons would produce a more complete picture.

The results are summarized in the table, which shows the presence and frequency of each species at each of the six ponds. The table also provides the number of species found and the "integrity coefficient" for each pond: a ratio of the number of native species to the number of introduced (adjusted by adding a point for each species of conservation concern).

EXPLANATIONS TO THE TABLE

Plant grouping and listing order
Plants are grouped into categories that are arranged in the following order: water plants; grasses, sedges, and rushes; ferns; other herbaceous plants; herbaceous vines; woody vines; semi-woody plants; shrubs; trees; and conifers.) Within each group, the order is alphabetical (by Latin name).

Coding for native, non-native, and invasive plants
Letters N or I following a species' name in the column "Status" are to be read, respectively, "Native" and "Introduced." For a few species there is no consensus as far as their nativity in SE Massachusetts. These are marked "N?" or "I?". The following standard letter codes are used for native plants of conservation concern: SC = Plant of Special Concern; WL = Watch-Listed Plant (endangered or threatened plants not found).

Introduced plants officially black-listed in MA are labeled 'INVASIVE' (in capitals). We have found certain plants to be invasive, even though officially they have not yet been listed. These are marked "invasive" in small letters.

Frequency/presence color coding
Frequency of each plant on each pond was assessed using a five-step scale: solitary—rare—occasional—frequent—common. These five gradations are shown in gray color of variable intensity. In addition to this scale, whenever a plant formed a significant clump/thicket/grove and was not found outside this discrete aggregation, we recorded is as "a clump/grove" (showed in green). In cases when frequency could not be assessed, plants were recorded as "present" (showed in yellow). If a plant was not found, the corresponding area is left blank (white).

Latin plant names are linked to respective Salicicola photo gallery pages containing photos of the species taken elsewhere in Massachusetts. Photos from the Six Ponds are available at the Six Ponds Photo Gallery along with maps.