Issue link: http://read.uberflip.com/i/974994
WWW.POTATOGROWER.COM 31 SCENARIO 1: Hairy nightshade is the only weed present in the field. It would be easy to use only one herbicide. On the other end of the stick, use the same two- or three-way tank mix that is planned for other fields, which have more than just hairy nightshade. Absolutely apply more than one herbicide in this scenario. Remember the basics, though: different mechanisms of action, all of which have activity on hairy nightshade. A few of the possible pre-emergence- applied combinations could be Outlook (dimethenamid-P) with Eptam (EPTC), Chateau (flumioxazin) plus Dual Magnum (S-metolachlor), or Matrix (rimsulfuron) with Reflex (fomesafen), both applied pre-emergence or Reflex pre- followed by Matrix post- emergence. SCENARIO 2: Hairy nightshade and common lambsquarters exist in the same field. This situation is a little trickier because many of the herbicides that control hairy nightshade well do not provide effective common lambsquarters control. Therefore, it can be challenging to find herbicides with the needed characteristics, and a two-way mix might not be the best. University of Idaho research has shown that pre-emergence-applied Linex (linuron) has activity on hairy nightshade and controls common lambsquarters in potatoes. Prowl H2O (pendimethalin) controls common lambsquarters. A three-way tank mixture of Outlook + Linex + Prowl H2O would provide two herbicides that control the nightshade and two that are effective on common lambsquarters. Here, metribuzin could be substituted for Prowl H2O, unless that common lambsquarters population is metribuzin-resistant. Remember, this three-way mix would not be the right mixture for Scenario 1, where only hairy nightshade was present. In summary, target the weeds in each potato field; don't use a shotgun approach. Weed populations resistant to metribuzin or other herbicides are out there, and the potential for an increase is also available, unless proactive measures are taken by using the most appropriate herbicide tank mix. 170758TriMfg12h.indd 1 2/16/18 2:27 PM M ake plans to attend the 2018 Potato Association of America meeting, July 22-26 at the Boise Centre in beautiful downtown Boise, Idaho. Besides fun activities such as a Basque street party and a field tour, the research and extension sessions will be very good informative, as well. Featured Monday, July 23 will be an industry session and symposium: "The Impact of Quarantined Pests on Potato Production." One-day registration is available for those who want to attend Monday only. The Tuesday and Wednesday sessions will include presentations on physiology; breeding and genetics, plant protection, marketing and utilization, extension, production and management. Visit www.uidaho.edu/PAA2018 for more information on registration and events. Check often, as the session program is being developed. Production." One-day registration is available for those who want to attend Monday only. The Tuesday and Wednesday