stickseeds

Stickseeds is a colloquial term used for seeds or fruits that adhere to passing animals, clothing, or fur, enabling dispersal through hitchhiking. The term is not a formal taxonomic designation but describes a convergent dispersal strategy found in several plant groups.

Morphology and adhesion mechanisms vary among stickseeds. Some have burrs or barbed projections that mechanically cling to fibers, fur, or feathers. Others feature mucilaginous coatings that swell and stick when wet, while some produce sticky secretions or viscid threads that bind to surfaces. The combination of surface texture and moisture sensitivity often determines how effectively a seed sticks and how far it can travel.

Representative examples and groups often associated with stickseeds include certain Hackelia (stickseed) species in North America, which produce burs that readily cling to fur and clothing, as well as various Bidens species (beggar-ticks) whose two-pronged or hooked seeds catch on textiles or animal fur. Other plants with burr-like fruits or hooked seeds can function similarly, contributing to epizoochorous dispersal.

Ecology and distribution: stickseeds occur in diverse habitats, including meadows, forests, and field margins, primarily in temperate regions. Their seeds are typically produced in large quantities, increasing the likelihood of attachment and successful disposal to new locations.

Impact and management: stickseeds can influence weed spread and agricultural management by facilitating the movement of seed material between fields or through animal hosts. Handling and removal practices focus on preventing attachment to clothing or equipment and promptly removing seeded plant material from habitats.

Research often centers on seed surface structures, adhesion chemistry, and ecological consequences of hitchhiking dispersal across plant communities.