Issue link: http://read.dmtmag.com/i/489844
8 APRIL 15, 2015 GOOD FRUIT GROWER www.goodfruit.com G ood weed control is essential during the early lives of trees in high-density apple orchards, as growers are intent on growing them to the top trellis wire in the first two years after planting. What is "good weed control?" Essentially, it means suppressing weed competition in a yard-wide strip where the trees are growing during the months of May through July. "Good" means keeping ground cover from other vegetation to less than 20 percent of the surface area. Deborah Breth, a tree fruit educator in the Lake Ontario Fruit Program, part of the Cornell University's extension program in New York State, credited Cornell's Dr. Ian Merwin and his research in the 1990s with establishing those critical times and strip width. In studies since then, those princi- ples remain the same, even as much else has changed. Trees have gotten smaller but are planted closer together, so there is more competition between trees and less shade from the canopy to suppress competition from other vegetation. Irrigation has joined weed control as important practices for good tree growth. Herbicide programs can be expensive, costing $60 to $150 per treated acre per year ($20 to $50 per acre of orchard), Breth said, but the cost of weed management is less than 1 percent of the annual cost of production and should not be considered an important factor in choosing herbicide. The economic impact of poor control can be great. "There is a potential for $1,600 to $2,900 per acre lost in Gala yield by the third leaf if weeds are not controlled in May through July," Breth said. Those numbers were based on studies at Cornell. One problem most herbicide programs share is length of control. "No pre-emergence herbicide in our plots gave season-long control," she said. Using Prowl (pendimethalin), Surflan (oryzalin), or Sinbar (terbacil) as the basic residual herbicide will give control lasting 30 to 40 days, she said. Adding Chateau (flumioxazin) will extend that to 40 to 60 days. Adding GoalTender (oxyfluorfen) will get 60 to 70 days. BEATING the competition Soils and Weed Control In young orchards, good weed control is essential for fast, early growth and high yields. by Richard Lehnert COURTESY OF DEBORAH BRETH Tests on critical timing of weed control were conducted last year in this planting of Gala on Malling 9 at a 3-by-12-foot spacing. VAPOR GARD ® FOR CHERRIES SEE LABEL FOR ADDITIONAL INFORMATION AND ALWAYS READ AND FOLLOW LABEL DIRECTIONS N o G e n e r ic S u b s t i t u t e ! A CONSISTENT PERFORMER CONFIDENCE Comes from 40 years and over 150,000 acres treated with VAPOR GARD. That's why many Growers, Consultants, Pest Control Advisors and Packing Houses understand VAPOR GARD's BENEFITS and VALUE on CHERRIES. MILLER CHEMICAL & FERTILIZER LLC 800-233-2040 ➤Increased size & yield with early application ➤Reduced splitting from untimely rain ➤Increased shelf life for greener stems !"!" " ""! !"! ! "! """!!!" " ! !""!"" ! !" """!!!"!"""" !" "!"""!"!""! """""" " """" "! !"" " !"!" " " "! " " !"" !" !""" ! "" !!! "!" !"" ! """!!"""! !"" ! ! "" " "" " " !" !!""" " !