Vol. 54—2000 - NorthEastern Weed Science Society

FIELD TRIAL RESULTS WIlli
SMOLDER: A BIOHERBICIDE FOR DODDER CONTROL
T. A. Bewick, J. C. Porter and R. C. Ostrowski'
ABSTRACT
Field studies were conducted in 1998 and 1999 to determine the optimum rates of application for
a preemergence (PRE) and a post-emergence (pOST) formulation of Smolder bioherbicide. The
active ingredient of the bioherbicide is the fungus Alternaria destruens. Studies were conducted
in cranberry in MA and carrot in WI. In 1998, PRE results were inconclusive. In 1999, however,
results in both locations indicated that a formulation produced by Sylvan, Inc., applied at 60 lb.
of product per acre, was effective in controlling dodder. In WI carrot trials, this rate of product
completely controlled dodder for the entire season. In both years and in hoth locations, dodder
infestation was reduced at least 90% by POST application of 10 10 viable candia per acre. In
1998, yield of carrot was significantly increased by this application. Based on these results, and
results of previous non-target plant studies and toxicity testing, an Experimental Use Permit will
be sought for the 2000 growing season.
'Extension Professor, Research Assistant, UMass Cranberry Experiment Station, East
Wareham, MA 02538 and United Agri-Products, PO Box 2010, Blue Jay, CA 92317.
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