Ceasarweed or Caesar’s weed is yet another Florida Exotic Pest Plant Council Category 1 invasive pest plant found at the Oslo Riverfront Conservation Area. Its dime-sized, pink flowers appear to be tiny hibiscus flowers, and, indeed, this plant is a member of the Malavaceae (hibiscus) family. Note the not yet ripe fruits in the picture above.
Now note the ripe ‘hitch-hiker’ fruits festooning Peter Sutherland (Class of 2001), after an invasive plant workday in 2005. Tiny star-shaped sticky ‘spines’ grab onto anything soft, including animal hair and clothing. Relatively large and heavy, these ‘burrs’ are unlikely to be spread far by birds. Mammals, especially humans, are the dispersal agents on which this ‘camp-follower’ relies.
Of Asia origin, this hitch-hiker thrives along the trails at the Oslo Riverfront Conservation Area and other places where humans go, seen below trying to overtake beautyberry (Callicarpa americana) and wild coffee (Psychotria nervosa).
Its leaves are quite distinctive in shape, so, please pluck up seedlings if you see them. They pull out very easily and satisfactorily.
Please be careful not spread this hateful hitch-hiker at the Oslo Riverfront Conservation Area or to other locations. Properly dispose of any hitch-hikers that attach themselves to you in the trash!
Categories: Invasive pest plant
Oslo Riverfront Conservation Area 
Do you know the name of the Asian origin hitch hiker shown in the photo?
The name of the plant is caesarweed (Urena lobata)