Horseweed

Scientific Name: Conyza canadensis

Weed Family: Asteraceae

Description

Horseweed is an annual weed, winter or summer, depending on location. Horseweed is an upright growing plant and can reach 4 – 5 feet if not mowed. Horseweed grows in a basal rosette. The leaves which are oblanceolate in shape are 3- to 4-inches in length. The leaves alternate and have margins that are toothed. The stem of horseweed is simple and unbranched, and covered with hair. Horseweed has a taproot. The inflorescence is a panicle of heads with pink to white flowers. Horseweed spreads by seed produced in the summer. Horseweed is found through out the United States.

Herbicide Use

Make a pre-emergence herbicide application prior to the seed germination. For post-emergent control use a product containing MSMA.

Distribution

Germination Dates

Zone-3: May

Zone-4: May

Zone-5: May

Zone-6: April

Zone-7: April

Zone-8: March

Zone-9: March

PBI-Gordon Product Recommendations

Post-Emergent

SpeedZone® EW Broadleaf Herbicide for Turf

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Post-Emergent

SpeedZone® Southern EW Broadleaf Herbicide for Turf

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Post-Emergent

Trimec® Southern Broadleaf Herbicide for Sensitive Southern Grasses

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Post-Emergent

Trimec® Classic Broadleaf Herbicide

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Post-Emergent

Trimec® 992 Broadleaf Herbicide

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Post-Emergent

Trimec® 1000 Low Odor Broadleaf Herbicide

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Post-Emergent

PowerZone® Broadleaf Herbicide

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