- Conyza canadensis is an annual with a long taproot and one or more stems arising from a basal rosette, normally about 3.3 ft. (1 m) tall.
- Leaves are up to 4 in. (10 cm) long and about 0.4 in. (1 cm) wide with some shallow teeth, green with some scattered hairs. Leaf margins ciliate and with longer hairs towards the base of the leaf.
- Flower heads are very numerous on short pedicels, only 0.08-0.12 in. (2-3 mm) in diameter. Disc florets are yellow, contrasting with distinct white ray florets which are 0.02-0.04 in. (0.5-1 mm) long.
- Fruit is light brown and has tufts of white or light brown hair. Seeds 0.04-0.05 in (1-1.3 mm) long with 10-25 off-white pappus hairs, 0.08-0.16 in. (2-4 mm) long.
- Ecological Threat
- Conyza canadensis is a common weed in temperate to tropical regions, preferring disturbed sites such as vacant lots, pastures, and on roadsides. This plant is native to North America.
Image Sets View other image sets:
EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org
State Invasive List - This map identifies those states that list this species on their invasive species list. For more information, visit Invasive.org
Most Troublesome / Most Common Agricultural Weed List
This map identifies those states that consider this species either most troublesome or most common in at least one commodity. For more information, visit the MTMC project page.
|No Data for this state|
|Troublesome or Common weed in one or more crops|
Invasive Listing Sources
Other System LinksPlants: COCA5
NPDN Pest: PBFAYBA
NPDN Host: 28137
|Common Name Reference:|| Weed Science Society of America Common Names List|
|Scientific Name Reference:||USDA, NRCS. 2010. The PLANTS Database. National Plant Data Center, Baton Rouge, LA, USA.|