Ten-year persistence of native plant species on a green roof in Northeast US

Abstract

We evaluated persistence of 28 northeastern or Midwestern US native plants for 10 y after installation on the green roof of the Wellesley College Water Treatment Facility. After 10 y, 50% of the original 28 species had perished and 29% had greatly expanded their presence on the green roof. Allium cernuum Roth (nodding onion; Liliaceae), Antennaria plantaginifolia (L.) Richardson (pussytoes; Asteraceae), Arctostaphylos uva-ursi (L.) Spreng. (kinnikinnick; Ericaceae), Campanula rotundifolia L. (bluebell bellflower; Campanulaceae), Carex pensylvanica Lam. (Pennsylvania sedge; Cyperaceae), Eurybia divaricata (L.) G.L. Nesom (white wood aster; Asteraceae), Fragaria virginiana Duchesne (Virginia strawberry; Rosaceae), (Oligoneuron album (Nutt.) G.L. Nesom (prairie goldenrod; Asteraceae), Schizachyrium scoparium (Michx.) Nash (little bluestem; Poaceae), Solidago sciaphila Steele (shadowy goldenrod; Asteraceae), and Symphyotrichum laeve (L.) A. Löve & D. Löve (smooth blue aster; Asteraceae) were able to persist and grow in response to the challenging green roof conditions, and we recommend them for use on green roofs. Twenty-seven emergent species were present on the green roof at the end of the study. Emergent Solidago L. (goldenrod; Asteraceae) species, Solidago caesia L. (wreath goldenrod), Solidago odora Aiton (anise scented goldenrod), and Solidago rugosa Mill. (wrinkleleaf goldenrod) should be investigated further for their suitability in green roof installations.