by Glen Arnold, Putnam County
Some clover fields in northwest Ohio are showing signs of field dodder. These appear as yellowing areas that could be confused with water damage. Dodder is a unique plant in the fact that it is parasitic. It must have a host plant to survive.
Dodder does not have any leaves or, for that matter, any chlorophyll to produce its own food. It lives by attaching to a host plant and extracting the host plant’s carbohydrates. The pale yellow color of the dodder plant makes the infested area of the clover field have a decidedly yellow color.
Dodder is an annual and is spread by seed. Having a hard seed coat, it is suspected that time and soil moisture levels control dormancy. How long the seed can survive appears to be variable.
For farmers who clip clover for seed, areas of the field known to have dodder should be avoided. Also, any clover seed harvested needs to be cleaned to avoid spreading dodder to other fields.
Glyphosate has been reported to control dodder post attachment and can be applied as a spot-treatment of a 1-2% solution to clover. However, be aware that there will be damage to the clover where the glyphosate is applied. Some farmers opt to hand-spray small patches of dodder to control its spread.