Common Name: dogfennel
Species: Eupatorium capillifolium (Lam.) Small
Bayer Code: EUPCP

Dogfennel is a perennial weed common to turf, roadsides and container plants. Depending on the management practices for the site, dogfennel can grow to be a very tall plant (exceeding 3 feet in height), or may reach maturity as a short plant (less than 6 inches). The finely dissected leaves of the plant make it easy to identify, and when crushed, the leaves and stems have a very distinct odor that is slightly sour and musty. The stems of dogfennel are soft and easily broken when young, but become very tough and woody as it ages. In addition, the stems are very conspicuously hairy, especially when young, but leaves are always hairless. Dogfennel could be confused with several other common turf weeds, including horseweed and mugwort. However, mugwort has very distinctive white wooly hairs on the underside of each leaf, and horseweed has elongated leaves with few to no serrations, and dogfennel has highly divided leaves.
dogfennel
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dogfennel seedling
dogfennel
 
CharacteristicTypeDescription
Growth Season perennial weed 
Growth Habit upright 
Leaflet Number one 
Leaf Margin lobed OR serrated/toothed 
Leaf Hairs none 
Leaf/Leaflet Shape   
Leaf Width   
Leaf Venation pinnate 
Leaf Arrangement alternate OR oppositelower leaves may be opposite, but upper leaves are alternate
Root Type fibrous 
Flower Color whiteinconspicuous, greenish-white