NEMATODES
PRE-PLANT TREATMENTS. Potential orchard replant sites should be prepared carefully. Before replanting old orchards, old roots should be removed. A cover crop should be grown for at least one season, preferably three seasons. Soil should then be worked to a good friable condition, free of plant residue and large clods of soil.
If there is need for nematode suppression, this can be done either by pre-plant fumigation, by the application of a systemic nematicide at or after planting, or both. Currently, the fumigation of New England orchard soils is not recommended because cooler soil environments have not proven to be conducive for supporting damaging levels of parasitic nematodes.
To determine if a nematicide treatment is economically feasible, nematode levels should be properly diagnosed. In addition, testing soils from old orchard sites for the severity of other disease pathogens is highly recommended for determining a proper control program prior to replanting.
POST-PLANT NEMATICIDES (For control of lesion, dagger and other parasitic nematodes.)
Nemacur 3:
(Non-bearing and bearing apple, cherry and peach trees) As a band treatment, 1.7 to 3.5 gallons of Nemacur 3 into 10-30 gallons of water for each acre of treated area. in 10 to 30 gals. of water per acre treated. Apply with an accurately calibrated boom sprayer (i.e. herbicide sprayer) in a 2-foot wide band on each side of the tree. Incorporate this product into the soil mechanically or supply sufficient irrigation (half-inch) immediately following application. Make the first application when trees have initiated new growth (within 2 weeks following planting). Do not apply more than 3.5 gals./acre per year per planting site. Special precaution: Do not apply within 72 days of harvest of apples or within 45 days of harvest of peaches or cherries. Do not feed cover crop grown in treated area to livestock. Do not add oil or surfactant to the spray mixture.Vydate L:
(Non-bearing apple, cherry, pear and peach trees). Use as a foliar treatment, as per label directions. Apply on a 2 to 3 week schedule for 4 applications. Apply first spray at first full leaf. Special precaution: Do not treat planting stock by root dip nor apply foliar sprays to trees under water stress.Replant disease problems and corrective practices are also covered in the New England Apple Production Guide and the Management Guide for Low-Input Sustainable Apple Production. For information on replanting orchard soils, parasitic nematode tests or replant disease severity bioassay, contact your state Cooperative Extension fruit tree specialist or plant pathologist responsible for fruit tree crops.