AppleTalk Conference Call Summary
Tuesday, July 22nd, 2014, 8:00 – 9:00 a.m.
Presenter: John Aue, Threshold IPM.
Moderator: Katherine Mumm, IPM Institute of North America; questions or comments, pwerts@ipminstitute.org
July 22nd Call download: Click Here
Announcements: USDA disaster assistance program
2014 Farm Bill is providing funding to specialty growers who have suffered a crop loss within the past two years. Contact your local USDA FSA office for more information. 2012 NAP Coverage for Frost, Freeze or Weather Related Fruit Losses Fact Sheet.
Heat stress and moisture minute 6:00
Dwarf trees, e.g., Bud 9 and M9, are beginning to show signs of drought stress despite adequate or excess rain during June. Visually inspect trees or use tensiometer to determine the utility of irrigating.
Fire blight 7:55
Surface sterilants, i.e., Oxidate (hydrogen dioxide) and ozone products, need to be applied prior to an infection. As shoot elongation ceases, trees become less susceptible to infection. If damage resulting from hail or high winds occurs streptomycin is the only material that will provide control; apply within 24 hours.
Sooty blotch and flyspeck 11:05
It is suggested to track rainfall from the date of the petal fall fungicide application until two inches, cumulative, of rain has fallen. At that point begin calculating leaf wetness hours (LWH). If two inches of rain has not fallen, begin calculating leaf wetness hours after 21 days. Mark date of either scenario and track leaf wetness hours to 185. It is important to apply/reapply fungicides for summer disease fungicides before 185 leaf wetness hours have been accumulated to protect against summer diseases. Sooty blotch and fly-speck can develop on stored apples if this criteria is not meet. Maintain this program for remainder of season, LWH from last fungicide application to harvest is included in this suggestion.
Codling moth: second generation biofix 13:40
Second generation flights begin between 950 and 1100 DD from first biofix. A variance of 150-350DD is recognized for this calculation. If the degree day criteria is meet and trap captures start building it is likely second generation flights have begun. An increase in trap counts before 950DD may indicate that traps were not set at the appropriate time for monitoring first generation. Moth captures immediately following the date traps are set may suggest flights began prior. When diagnosing damage considering insecticide efficacy as a result of biofix and/or weather conditions. If first generation was controlled there will be less activity during second generation. Spot spraying high activity blocks will provide adequate control; full cover applications may not necessary.
Apple maggot 21:50
Seven to ten days before harvest apples emit volatiles which will likely outcompete unbaited red spheres. As harvest approaches concentrate baited traps in late summer varieties, cultivars that ripen before Paula Red, to monitor pressure. In blocks with historic pressure baiting may not be necessary.
Stink bug 33:55
Stink bug populations have been down in the last two years. Green stink bugs are becoming more prevalent at this time in the season, potentially immigrating from alternate hosts. Populations are not a concern at this time, continue to monitor as the season progresses.
Obliquebanded leafroller 34:55
Obliquebanded leafroller (OBLR) populations are low this season, may be a result of OBLR concentrating on alternative deciduous hosts. Contact John or Peter if you have been catching larger than normal flights.
Apple curculio 40:15
Apple curculio (AC) is becoming an increasingly common pest in regional orchards. AC may become a difficult pest to control since damage is not easily distinguishable and materials applied at this time in the season do not provide adequate control.
Pest biology indicates that AC travels into orchard later in the season then plum curculio (PC) and has the ability to reproduce in apples. AC damage results in distinct scaring around the hole and looks similar to tarnished plant bug and PC feeding. While scouting look for fruit with holes all over the fruit. If damage is observed cut radially across the fruit to see how deep the larvae traveled, reproduction may have been successful if tunneling goes to the center of the fruit. Note: Tarnished plant bug feeding typically does not produce a visible scar. PC are emerging now to feed before migrating to hibernation sites, feeding is concentrated to the calyx end of the fruit.
Please contact John or Peter with any observations, e.g., location of damage, specific varieties, amount of damage, etc., you have regarding this pest.
Additional articles and resources
• 2012 NAP Coverage for Frost, Freeze or Weather Related Fruit Losses Fact Sheet. http://www.fsa.usda.gov/FSA/newsReleases?area=newsroom&subject=landing&topic=pfs&newstype=prfactsheet&type=detail&item=pf_20140714_distr_en_nap.html
