Extension Educator, Local Food Systems and Small Farms
Extension Educator, Horticulture
June 22, 2012
Apple and pear trees are also having their problems. There is a large amount of tip dieback in some varieties, and this is probably fire blight. Look for a shepherd's crook at the tip of the affected areas as a clue it is fire blight. Fire blight is a bacterial disease, therefore there is little chance for you to treat it. The common treatment in commercial operations is streptomycin, but it has to be applied before symptoms appear. I don't think you will get a prescription for that much antibiotic, so Bordeaux mixture can also help prevent the disease (applied before the infection next year). Prune out disease cankers when dormant. This disease cost Illinois its pear industry. Apple scab is also easily seen – once again.