Orchard notes, July 23

By Terence Bradshaw

We are in the quiet time of apple season, when growers and researchers alike can take a little time off. That said, recent heavy rain showers (ok, downpours) have likely removed fungicide residues in orchards several times this month. However, leaf wetness periods have been relatively short, so although there have been infection periods for sooty blotch and flyspeck, they have not been especially severe. Maintenance of fungicide coverage through August for wholesale fruit is still recommended, but retail and pick-your-own orchards can relax a bit.

Apple maggot fly are moving and will likely need or have already needed treatment in problem orchards. Orchards with history of light damage may get away with border row sprays, but whole orchard sprays are recommended for orchards with a history of even moderate damage. Of course, locating a red sticky ball in the orchard interior will let you know if the flies are active beyond the borders.

Codling moth second generation flight is beginning now. Plan to treat for this pest in about ten days, and use NEWA to most accurately time treatment.

All sprays at this time of year should include some form of calcium to improve fruit quality and avoid biter pit, especially on large-fruited cultivars like Honeycrisp and Cortland.

It is the time in the growing season to collect leaf samples for analysis. Samples are usually collected between July 15 – Aug. 15. The UVM Agriculture and Environmental Testing Lab can provide analysis, but at this time their output does not generate fertility recommendations. The following are potential options of labs for analysis. It is recommended that you contact the lab for instructions and costs before samples are sent. Plus, it is important to confirm that they will send recommendations along with the analysis.

(1) University of Maine Analytical Lab: http://anlab.umesci.maine.edu/

(2) University of Massachusetts Soil and Tissue Testing Lab: http://www.umass.edu/plsoils/soiltest/

(3) Cornell Nutrient Analysis Lab: http://cnal.cals.cornell.edu/