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Spectacle Island Plants

In a two-year project funded by the Island Alliance to study the vegetation of the Boston Harbor Islands National Park Area, 32 islands were surveyed and inventoried for vascular plant species. Field surveys began on 9 June 2001 and ended on 30 September 2002.

Below is the data collected for Spectacle Island.


Data Notes:
* = introduced species
(v) = voucher specimen
(p) = photograph

Due to formatting restrictions, species scientific names are not italicized in the data table.
Plant information on Spectacle Island
Species_Scientific_NameSpecies_Common_NameFamilyDate_ObservedHabitat

Notes on Habitats and Flora

There is little natural habitat on this reconstructed and revegetated island. Most of the island consists of grassy fields which have been extensively landscaped with native and non-native plants. This inventory list above attempts to exclude those recently landscaped species that have not become “naturally” established. This definition is somewhat arbitrary, and some species included here may not prove successful as naturally reproducing populations. In the Final Report, the Massachusetts Highway Department’s list of species that have been introduced to Spectacle will be included as a supplement to this list.

Vegetation that has truly naturalized on the island primarily inhabits disturbed, open grounds along the beachfront on Spectacle’s west side. Road edges, ditches, and seepages also have a number of naturalized species. Spectacle has no true wetlands, but wet spots at the base of slopes and along roadways, especially on the northern “mound”, have a varied assemblage of native wetland plants. The beach strand on the west side has plant associations similar to those of beach communities throughout the islands.

A population of two seabeach dock (Rumex pallidus) plants was the most surprising find on Spectacle. On June 30, two robust, mature plants were documented 200-250 feet north of the landing. One plant was located in disturbed ground just above the high tide line, and the second was growing in a roadway ditch. Compared with other Harbor Island populations of this species (on Bumpkin, Grape, and Peddocks Islands), this occurrence in disturbed grounds above the high tide line is unusual. On the other islands, where seabeach dock occurs, the plants grow in undisturbed habitat at the uppermost limit of sandy beach. How these rare plants arrived here is a mystery. One possibility is that the seed source came from the seabeach dock population that inhabited Thompson Island’s easternmost spit of land, which is approximately 0.5 mile by water west of Spectacle’s western beachfront. (The Thompson Island population, last documented in 1984, appears to be extirpated).

Boston Harbor Islands National Recreation Area

Last updated: September 8, 2021