What a Season

September 06, 2007

Just a few very late season peaches are coming out of orchards at this time. It's basically over and I know a lot of growers are glad to move on. This was a very difficult season with the April freeze. While the drought has been extreme, peaches remaining after the freeze were some of the tastiest I've had. Fewer fungicides and in some cases insecticides were needed and growers with marketable peaches took advantage of this situation.

End of the season chores that should be accomplished soon are 1) fertilization for fall and early spriing tree health, 2) peach tree borer sprays, 3) light prunning for water sprout removal and sanitation

Fertilization in late summer consists mainly of nitrogen applied at a rate of 1/3 the yearly total. This amount helps to improve overall tree condtions and encourages stronger bud development and winter hardiness for the 2008 season. Yearly nitrogen rates range from 60 pounds to 80 pounds of nitrogen per acre. So, 1/3 rates would be from 20 pounds to 26 pounds nitrogen per acre.

Borers come in two forms, Lessor Peachtree Borer, Synanthedon pictipes, and Greater Peachtree Borer, Synanthedon exitiosa. Lessor peachtree borers are will normally infest upper portions of the scaffold where cuts and wounds have occurred. Greater peachtree borers will infest the lower portion of the trunk and zone in contact with the soil. Insecticide applications should include both scaffold portions and lower trunk in order to protect from both of these pests. Sufficient water should be used to produce wetting around the soil trunk interface.

Prunning during the summer has been practiced by many growers for a number of years. This summer with the heat and water stress trees were under, many growers delayed or skipped summer prunning. Most trees have begun recovering well at this time. Growers desiring to reduce excessive shading of interior wood (fruit carrying growth) should be finishing this up now. Removal of water sprouts and a few thinning cuts are all that is needed in many cases. When removing interior growth be certain not to expose scaffolds to direct sun. Sun scalding of scaffolds can occur causing tissue damage on the upper suface of the scaffold and providing an entry point for wood rotting organisms.
Since trees are still recovering from the drought stress I would go light with pruninng. Remember, you will not produce new growth capable of fruit production next year when prunning this late in the season. What you leave is basically what you will be producing from next year.

Sanitation is always an important part of growing any crop, especially a perennial crop. Most of our efforts on sanitation should have been accomplished much earlier. When damaged fruit remained in orchards it was only a matter of time before insects and diseases attacked this fruit. In some orchards, severe brown rot infections began showing up in late July on damaged fruit. These fruit infections have led to shoot and branch infections. Where possible, prune out damaged shoots and destroy them. Disease cankers or lesions on wood remaining until spring will be a source for fruit infections next season.