Eutrochium maculatum

Eutrochium maculatum, the spotted joe-pyeweed,^[2] is a North American species of flowering plant in the family Asteraceae. It is widespread through much of the United States and Canada.^[3] It is the only species of the genus Eutrochium found west of the Great Plains.^[4]

Spotted joe-pyeweed
Portage, Michigan
Conservation status
Secure  (NatureServe)
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Asterales
Family:	Asteraceae
Genus:	Eutrochium
Species:	E. maculatum
Binomial name
Eutrochium maculatum (L.) E.E.Lamont
Synonyms[1]
Synonymy Eupatorium maculatum L. Eupatorium purpureum subsp. maculatum (L.) Á.Löve & D.Löve Eupatorium purpureum var. maculatum (L.) Voss Eupatorium trifoliatum var. maculatum (L.) Farw. Eupatoriadelphus maculatus (L.) R.M.King & H.Rob. Eupatorium maculatum f. eresinatum Lepage Eupatorium maculatum var. urticifolium Barratt ex Alph.Wood Eupatorium purpureum var. maculatum (L.) Darl. Eupatoriadelphus maculatus var. bruneri (A.Gray) R.M.King & H.Rob., syn of var. bruneri Eupatorium maculatum var. bruneri (A.Gray) Breitung, syn of var. bruneri Eupatorium maculatum subsp. bruneri (A.Gray) G.W.Douglas, syn of var. bruneri Eupatorium purpureum var. bruneri (A.Gray) B.L.Rob., syn of var. bruneri Eupatorium trifoliatum var. bruneri (A.Gray) Farw., syn of var. bruneri Eupatorium bruneri var. foliosum (Fernald) House, syn of var. foliosum Eupatorium maculatum var. foliosum (Fernald) Wiegand, syn of var. foliosum Eupatorium purpureum var. foliosum Fernald, syn of var. foliosum Eupatorium trifoliatum var. foliosum (Fernald) Farw., syn of var. foliosum

This herbaceous perennial sometimes grows as high as 2 m (6 ft 7 in). Stems are sometimes completely purple, sometimes green with purple spots. One plant can produce numerous rose-purple flower heads in late summer, each head with 8-22 disc flowers but no ray flowers.^[5] The specific name maculatum, meaning spotted, refers to the purple spots on the stem.^[6][4]

Spotted joe-pyeweed thrives in marshes, rich fens and swamps. It also does well in man-made moist expanses such as ditches, seepage areas and wet fields. Above all else the plant flourishes in the non-shaded environments that are also abundant in wetlands.^[7][8]

It is a larval host to the Clymene moth, the eupatorium borer moth, the ruby tiger moth, and the three-lined flower moth.^[9] The plant also attracts butterflies and honeybees.^[10][11]

Varieties

The following varieties are known:^[1][8]

• Eutrochium maculatum var. bruneri (A. Gray) E. E. Lamont - western Canada (British Columbia to Saskatchewan), western USA (Minnesota west to Idaho, south to Arizona + New Mexico)
• Eutrochium maculatum var. foliosum (Fernald) E. E. Lamont - eastern Canada (Newfoundland to Ontario), northern USA (Maine to Minnesota)
• Eutrochium maculatum var. maculatum - eastern Canada (Newfoundland to Ontario), eastern USA (Maine to Minnesota, south to northern Georgia)

Cultivars

The following cultivars are recipients of the Royal Horticultural Society's Award of Garden Merit (listed under the synonym Eupatorium maculatum):-

• (Atropurpureum Group) 'Orchard Dene' ^[12]
• (Atropurpureum Group) 'Purple Bush' ^[13]
• (Atropurpureum Group) 'Riesenschirm' ^[14]

Ottawa, Ontario