Leaf chopping (flail mowing) is done in fall or early spring to reduce scab inoculum.
Urea treatment is applied in fall or early spring to reduce scab inoculum.
Trees are pruned annually to remove diseased wood (primarily fire blight and black rot) and apple mummies (rot disease inoculum).
A dormant to green tip copper compound application is made to suppress fire blight.
First fungicide spray is delayed an appropriate time according to previous year's scab incidence using potential ascospore dose evaluation, and ascospore maturity level in the current season.
Unless visible infections develop, fungicides for scab management are applied only until the end of primary scab season, using 100% ascospore maturity and release and sufficient time to allow symptoms from the last infection to be visible.
Apple scab infection periods are measured using leaf wetness and temperature.
Fungicide treatments for primary apple scab are made according to infection periods, tree growth and estimates of the remaining effectiveness of the previous fungicide application.
Resistance management is considered when making fungicide applications, by either tank-mixing two or more modes of action in a single spray, or rotating modes of action such that materials in the same FRAC group are not applied consecutively.
Treatments for fire blight follow a fire blight forecast model (e.g. Maryblyt or CougarBlight), or specific Extension or consultant recommendations based on such a model.
Fungicide applications exclusively targeting powdery mildew or rusts are not made unless there is a history either disease in the block.
Where rust diseases are a problem, alternate hosts (primarily red cedar and juniper) within 300 feet surrounding orchard are removed.
Fungicides for sooty blotch/flyspeck are applied based on an accumulated wetting hours and estimated fungicide depletion.
Plantings are located so that trees are least 75 feet away from wooded or shrubby borders to reduce pressure from sooty blotch and flyspeck fungi.
Orchards are replanted with a minimum three-year gap between tree removal and new tree planting. During the gap, cover-crops selected to suppress nematodes, reduce soil compaction, improve weed suppression, and benefit soil health in general are planted.
On sites prone to flooding or with heavy soils, trees are planted on raised berms and/or drainage is installed.
Experimental block of disease-resistant trees is planted.