Attribution: Dick Culbert from Gibsons, B.C., Canada, CC BY 2.0, via Wikimedia Commons
.jpg){kind=link}
.jpg){kind=link}
❮
❯
Cobbler's Peg Weed (Bidens pilosa)
Common Names
- Farmer’s Friend
- Blackjack
- Spanish Needle
- Beggar’s Tick
Description
Cobbler’s Peg (Bidens pilosa) is an annual, fast-growing herbaceous weed belonging to the Asteraceae family. It is widely recognized for its distinctive seed heads that attach to clothing and animal fur. This weed thrives in disturbed areas, agricultural fields, roadsides, and gardens, especially in tropical and subtropical regions. It can grow up to 1.5 meters tall and is known for its resilience in various soil types.
Identification
Stems & Leaves
- Erect, slender, branching stems that are often reddish or green.
- Leaves are oppositely arranged, compound with 3 to 5 serrated leaflets.
- Leaflets are lanceolate, dark green, and slightly hairy.
Flowers
- Small, daisy-like flowers with bright yellow central discs.
- White or pale yellow ray florets (sometimes absent).
- Blooms throughout the year in warm climates.
Fruits & Seeds
- Produces slender, black, barbed seeds (achenes) with two to four hooked bristles.
- Seeds easily attach to clothing, animal fur, and machinery, aiding in dispersal.
Spread
Cobbler’s Peg spreads primarily through its sticky, hooked seeds, which cling to people, animals, and objects. It also spreads via water movement and contaminated soil or agricultural equipment. The plant is highly prolific, producing thousands of seeds per plant, which can remain viable in the soil for years.
Similar Species
- Bidens alba (Shepherd’s Needle) – Similar in appearance but with more prominent white ray florets.
- Bidens bipinnata (Spanish Needles) – Has more finely divided leaves and slightly different seed structure.