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Snake 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 Snake 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 Snake Island
Species_Scientific_Name Species_Common_Name Family Date_Observed Habitat

Notes on Habitats and Flora (2002)

The western side of this small island has one of the finest salt marshes of any of the Harbor Islands. Saltmarsh species include Distichlis spicata, Elytrigia pungens, Limonium nashii, Spartina alterniflora, Spartina patens, Salicornia maritima, Sueada linearis, and Suaeda maritima. Spartina alterniflora dominates the mudflats surrounding much of the island. Patches of sandy beach with typical beach strand vegetation (such as Ammophila breviligulata, Atriplex patula, and Datura stramonium) occur on the island’s eastern and southern shorelines.

Cottonwood (Populus grandidentata), quaking aspen (P. tremuloides), and big-tooth aspen (Populus grandidentata) dominate dense thickets on the east side of the island. These young, early-successional trees grow to about 20 feet in height. Although dense, these thickets have a relatively low diversity of plants. Phragmites is common in the wooded thickets, growing vigorously under the aspens.

Most of the island’s small area of uplands consists of low, semi-open scrub thickets dominated by small staghorn sumac shrubs (Rhus typhina) growing 3-5 feet in height on dry, sandy, and stony soils. Common mugwort (Artemisia vulgaris) is abundant in these low thickets. Small patches of old fields with perennial forbs and grasses (examples— Aster ericoides, Festuca rubra, Phalaris arundinacea, and Solidago sempevirens) are interspersed among the scrub thickets.

Common reed (Phragmites australis) grows throughout the island, in a variety of habitats, and dominates large stretches of upper beach and edges of salt marsh. Its presence blights what is otherwise a relatively healthy, attractive, and “native” (for the Harbor Islands) mosaic of plant communities on this small island. Removal of this species may be possible here (replacement by Typha angustifolia?).

Boston Harbor Islands National Recreation Area

Last updated: August 31, 2021