Damage and Recovery of Cranberry Vines from Exposure to Handheld Flame Cultivators

Abstract

Damage and recovery responses of four cranberry varieties (‘Mullica Queen’, ‘Crimson Queen’, ‘Stevens’, and ‘Howes’) to handheld propane flame cultivation (FC) torches were evaluated. All combinations of four levels of exposure duration of three FC torches (open flame 0, 3, 6, and 9 seconds), infrared (IR) and IR with a 4.5-cm metal spike (0, 15, 30, and 45 seconds), were tested on rooted cranberry uprights (vertical stems) planted in clay pots. Pots were subjected to a single treatment from one FC torch at one exposure duration; a glyphosate wipe was also included as a treated control (industry standard). Treatments were replicated five times. All cranberry plants were damaged by all levels of exposure duration as evident by visual damage ratings, reduced net cumulative stem lengths, reduced number of uprights, and reduced proportion of reproductive uprights when compared with untreated plants. All cranberry plants treated with glyphosate had total mortality; all cranberry plants from all varieties treated with FC survived, and all had net positive stem growth in the year after treatment except for ‘Stevens’ treated with open flame and IR with spike. The non-fatal response of cranberry to FC indicates that FC will cause less damage than glyphosate to cranberry plants that are incidentally exposed during spot treatment of weeds and thus could be integrated into weed control in certain situations, including organic farming.