G.L. Graham and D. Savoie
Abstract: Volunteer potatoes (Solanum tuberosum) can be a weed problem in the year following a potato crop.
Volunteer potatoes are difficult to manage in rotational crops and no one specific measure will guarantee complete
control. An integration of different control measures, including herbicide use in rotational crops, is required. Herbicide
options should be evaluated to ensure proper recommendations can be made for New Brunswick producers when
dealing with volunteer potatoes. A trial was established in a commercial barley (Hordeum vulgare) field in Lower
Portage, New Brunswick, the year following potato production when a large number of tubers were left in the field
following harvest. The level of potato volunteer control was quite variable across the trial, most likely due to late
potato emergence. The most promising treatments included dicamba and fluroxypyr mixes. Pyrasulfotole/bromoxynil
was effective at the early rating time, although control decreased as the trial progressed. All tested herbicides, except
fluroxypyr alone, gave adequate control of lamb's quarters. Fluroxypyr is not currently registered for use in New
Brunswick. From a producer's perspective with respect to control of potato volunteers, herbicide choice in cereals may
not be as important as application timing. in order to make the correct choice of herbicide, the spectrum of weeds in the
field should be considered as all herbicides have strengths and weaknesses with respect to weed control.