Although Dodder vines grow throughout the spring and summer, they are most noticeable in late summer into fall. The yellow or orange vines draped over other plants in sometimes thick blankets is eye catching. The long, thin, waxy stems do earn their common name of witch’s hair.
June to October N Family: Convolvulaceae
Flower: Groups of flowers open along the stems throughout the blooming time. The flowers can be insect pollinated or will self pollinate. The flowers are white. They have three to five sharply pointed corolla lobes, depending on the species. These lobes can curve inward or flare slightly.
Leaf: If rudimentary leaves are present, they are alternate. Any leaves present are reduced to flaps. They have the same color and look as the stem, containing no chlorophyll and are incapable of photosynthesis.
Stem: Annual, thin, white to yellow to orange, waxy stems twine around and sprawl across host plants. Periodically hastoria or suckers pierce the host plant stem to divert sap into the dodder stem. Stems can be several feet in length.
Root: The seed puts out a root which withers away when the stem finds a host plant or a few days pass even if no host plant has been found.
Fruit: The seed capsules are globular and turn brown at maturity. The seeds can be spread by wind or water.
Habitat: This plant prefers full sun and moist areas but will grow wherever host plants grow. Each dodder species can parasitize more than one species of plant.
Field, Buttonbush, Compact, Rope, Common, Pretty,
Smartweed, Hazel, Cusp, Witch’s Hair
All Dodders are parasitic producing no chlorophyll themselves. If the germinating sprout doesn’t find a host plant within a day or so, it will die.
Dodder vines are like long, thin spaghetti with a waxy coating. Different species vary in color but fall in the white to yellow to orange range. The mass of such color can be striking.
Some of the Dodders can be identified in the field. Rope Dodder forms thick coils of stems, flowers and seed capsules. Buttonbush Dodder has four lobes in its flower. Most require careful study of the flowers under magnification so they are treated as a group here.
The different Dodders may have a preferred host plant but are not confined to that one plant. That makes identification by the host plant unreliable.
Dodder can overwhelm the host plants and kill them.