Eutrochium maculatum

Spotted joe-pyeweed
Portage, Michigan
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	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

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

Eutrochium maculatum is an herbaceous perennial sometimes growing 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 binomial name maculatum, meaning spotted, refers to the purple spots on the stem.^[6][7]

Spotted Joe-Pye weed 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 so abundant in wetlands.^[8][9]

Varieties^[1][9]

• 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)

References

1. The Plant List, Eutrochium maculatum (L.) E.E.Lamont
2. "USDA GRIN Taxonomy".
3. Eutrochium maculatum, Natural Resources Canada
4. Biota of North America Program 2014 county distribution map
5. RHS A-Z encyclopedia of garden plants. United Kingdom: Dorling Kindersley. 2008. p. 1136. ISBN 1405332964.
6. Dickinson, T.; Metsger, D.; Bull, J.; & Dickinson, R. (2004) ROM Field Guide to Wildflowers of Ontario. Toronto:Royal Ontario Museum, p. 164.
7. Biota of North America Program 2014 county distribution map
8. "Eutrochium maculatum var. maculatum". New York Flora Association. 2005. Retrieved 2008-09-24.
9. Flora of North America, Eutrochium maculatum (Linnaeus) E. E. Lamont, 2004. Spotted joepyeweed, eupatoire maculée

Ottawa, Ontario