Integrated Pest Management
Prickly Lettuce
Lactuca serriola
Description
- tall (1 – 5 feet); thick stem; branches occur toward top of plant when flowering
- mature leaves have a wavy appearance with deep lobes attached tightly to the stem
- the underside of the leaf midrib and stem have prickly hairs, giving the plant a “sticky” feel
- when broken, the plant exudes a milky substance
- light yellow flowers give rise to seed clusters with white fluffy plumes that help the seeds float to a new location
Location
- gardens, cropland and open spaces
Life Cycle
- biennial or winter annual; reproduces only by seed
- most seedlings germinate in the fall in a rosette form with a long taproot that overwinters
- some seedlings emerge in spring
- stem development and flowering happens mid-summer to late fall, then the plant dies
IPM Recommendations
- Hand-pull plants in planting beds prior to seed maturation.
- Maintain healthy, competitive desirable vegetation.
- Apply an appropriate post-emergent herbicide directly to target weeds.