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Picture of the Week
for 14 August 2000


Dodder in flower bed
Dodder in Flower Bed
Dodder Close Up
Dodder photo, courtesy of Gary Michel, AgNR Extension Educator, Warrick County. (Click on smaller photo to see larger photo.)

The following information is from Down the Garden Path, Issue #84 (PDF 104K), August 14, 1995.

Dodder, Cuscuta sp. -- Attack of the String Monster!

B. Rosie Lerner, Consumer Horticulture Extension Specialist

If you've run across a stringy yellow mass attacking your garden, don't panic. No, it isn't a visitor from another planet, but it may be a plant that sounds like it belongs in a low-budget science fiction movie!

Dodder is a parasitic weed that must obtain its moisture and nourishment by attaching to a green, living plant. It belongs to the Morninglory family, but it bears little resemblence to the garden types, other than its vigor.

Dodder is an annual that reproduces by seed. As the seedlings emerge, they begin twining around any type of support that might be available, especially garden plants. The yellowish-orange, string-like stems form dense masses while sending root-like projections into the host plant (your treasured flower, vegetable, or shrub!)

The plant appears to be leafless but may in fact bear tiny bracts. The clusters of tiny white flowers eventually give rise to small pods containing seed, providing opportunity for dodder to invade your garden in future years!

Now for the really bad news. There is no herbicide that can be applied to garden or landscape plants once dodder is growing on those plants. Hand-pulling and pruning is the only method of control once the dodder is established. Prior to germination, dodder can be prevented reasonably well with the application of a pre-emergence herbicide called Dacthal. Be sure to read and follow all label directions before using any pesticide.

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