Encyclopedia Article

Dodder                          Cuscuta spp.

Family: Convolvulaceae (Formerly in Cuscutaceae family)
Life cycle:  Annual
Native status: There are native and exotic dodder species
Habitat:  Landscapes, nursery crops, alfalfa, other sites with appropriate hosts

General description:  A parasitic vine that lacks chlorophyll and distinct leaves.  Thread like stems are yellow or orange and twine around host plants.  Roots sustain the plant until it is 2-5 in long, and then the seedling attaches to a suitable host and the root ceases functioning.  Can form dense mats that smother the host.  Flowers are small, white to pink, and occur in clusters.

Key ID traits:  Yellow, leafless vine attached to host plant.

Miscellaneous:  Many dodder species are found throughout the U.S.  They vary widely in their host specificity.  In Iowa, alfalfa and other legumes, ragweed, goldenrod and chrysanthemums are hosts commonly attacked by dodder.

Dodder on common ragweed in greenhouse.  


Haustoria on dodder stems penetrate the host and remove nutrients required for growth of the parasitic plant.

Dodder infecting goldenrod in a prairie.