Eupatorium Genus boneset; eupatorium Asteraceae

 

Eupatorium perfoliatum, pond margin, Falmouth, MA , 8/2015

Eupatorium perfoliatum, MBGargiullo. pond margin, Falmouth, MA , 8/2015

Eupatorium is a genus of perennial herbs, mostly not branched below inflorescence. 

Leaves opposite, sometimes whorled, or upper leaves alternate, blade often with 3 major veins; lower leaves smaller than upper and deciduous as plant flowers. 

Eupatorium dubium.flower.Richard Payne.Falmouth, MA.8/15/15

Eupatorium dubium.flower.Richard Payne.Falmouth, MA.8/15/15

Eupatorium hyssopifolium.Jason Sachs.New England Wild Flower Society.gobotany.newenglandwild.org.jpg

Eupatorium hyssopifolium.Jason Sachs.New England Wild Flower Society.gobotany.newenglandwild.org.jpg

Flowers white to dull purple, very small, all tubular (discoid), petal lobes 5, pointed, no rays; in dense, mostly 5-flowered heads, on a bract covered floral base (involucre) 0.1-0.3 cm wide, bracts in 2-3 rows, usually green, hairy, often with membranous margins; inflorescence branched. 

Eupatorium hyssopifolium. By CONN Herbarium. Copyright © 2018 CONN Herbarium. U. of Connecticut Herbarium. bgbaseserver.eeb.uconn.edu

Eupatorium hyssopifolium. By CONN Herbarium. Copyright © 2018 CONN Herbarium. U. of Connecticut Herbarium. bgbaseserver.eeb.uconn.edu

Fruit dry, small, 1-seeded (achene), 5-angled (use lens), plume of bristles in one row (Flora of North America 1993+).

Notes: Fed upon by larvae of the Haploa clymene moths.

Haploa clymene. Harry Zirlin, Westchester Co., NY, 8/2017

Haploa clymene (clymene moth). Harry Zirlin, Westchester Co., NY, 8/2017