|Pierce, Francis - WASHINGTON STATE UNIV|
Submitted to: Potato Progress
Publication Type: Popular Publication
Publication Acceptance Date: February 1, 2005
Publication Date: March 1, 2005
Citation: Boydston, R.A., Pierce, F., Spellman, D.E. 2005. Volunteer potato outlook for 2005. Potato Progress. 5(4):1-3. Technical Abstract: Unharvested tubers left in the ground during potato harvest often overwinter in regions with mild winter temperatures resulting in a serious and difficult to control weed problem in the following crop. Potatoes normally are killed when they reach temperatures below 28 F. Soil temperatures at the two inch depth near Odessa, WA reached 26 F in early December, 2004, adequate to kill only shallow buried potato tubers. In the lower Columbia Basin, soil temperatures at two inch depth never reached lower than 30 F the entire 2004-05 winter season. Based on weather station data, the coolest air temperatures occurred early- to mid-January 2005 in the Columbia Basin. However, significant snow cover during this period prevented soil temperatures from dropping below 31 or 32 F. Examination of potato fields near Prosser and Paterson, WA in early February, revealed that potato tubers were killed only to 2.5 inches deep and tubers buried deeper were intact and viable. Tuber mortality in the lower Columbia Basin will be minimal and we predict major volunteer potato populations in 2005. Recommendations for controlling volunteer potato in rotation crops are summarized.