The 2011 ASHS Annual Conference

Four weed management strategies were established in 2009 and continued into 2010:  1) periodic mowing; 2) Herbicide 1, herbicide application as needed from June to July; 3) Herbicide 2, application as needed from June to August; and 4) bark mulch applied once in 2009.  The herbicide GreenMatch which contains the active ingredient d-limonene was applied at the labeled rate in a one-meter band under the trees.  Bark mulch was also applied in a one-meter band.  The orchard was planted in 2007 with ‘Honeycrisp’ and ‘Snowsweet’ on M.26 rootstock. Bark mulch continued to suppress weed growth in 2010.  Herbicide and mowing both reduced weed biomass but not as much as mulch.  Mulch increased trunk and shoot growth compared to herbicide and mowing.  Tree growth with both herbicide treatments was similar to mowing.  Leaf level of N was lower in mulched trees compared to Herbicide 1, but was similar to mowing and Herbicide 2.  The effect of weed management strategies on soil moisture was inconsistent throughout the season.  Mulch had greater soil moisture than mowing May 27 through June 4 and again from July 7 to Aug. 30, but similar soil moisture level at other dates.  The Herbicide 1 treatment did not increase soil moisture compared to mowing.  Herbicide 2 increased soil moisture from July 29 to Aug. 30, but was similar to mowing on other dates.  Mid-day stem water potential was not affected by weed management strategies.  Trees were in their first cropping year, but the relative amount of bloom per tree and fruit yield at harvest were not affected by weed management strategies.Four weed management strategies were established in 2009 and continued into 2010:  1) periodic mowing; 2) Herbicide 1, herbicide application as needed from June to July; 3) Herbicide 2, application as needed from June to August; and 4) bark mulch applied once in 2009.  The herbicide GreenMatch which contains the active ingredient d-limonene was applied at the labeled rate in a one-meter band under the trees.  Bark mulch was also applied in a one-meter band.  The orchard was planted in 2007 with ‘Honeycrisp’ and ‘Snowsweet’ on M.26 rootstock.