The symptoms of fireblight infection of a rootstock are a watersoaked appearance, discoloration, and ooze. Dead leaves cling to tree, and this is a key diagnostic feature. The leaves of infected areas blacken first along midrib and veins before becoming fully black. On older trees the first sign is often a discrete area of dead, burnt looking, black leaves (in an area where no other injury has been sustained). On young trees, it is easy to spot red water-soaked lesions that in warm weather trickle a sticky, oily, orange-brown ooze. When fireblight infects growing shoots, the tips of shoots wilt and droop to a “shepherds crook” form. Look for small droplets of white or amber ooze on discolored plant tissue. The tissues of the ovary and peduncle (stem) shrivel and turn to brown then black. Infected flowers become water soaked and a dull greyish-green. One of the main points of entry is bloom in spring. Infections can also travel inside tree and become symptomatic at a point distant from the original site of infection. The dreaded fireblight "strike" can appear on any part of tree. Injured tissue is especially vulnerable to infection, and a hailstorm can devastate an orchard by inflicting countless tiny injuries through which the bacterium enters each tree. It spreads rapidly in moist, warm weather, especially during bloom. Ideal conditions for bacterial reproduction are 70-85☏. Fireblight bacteria grow by cell division, and this process is regulated by temperature. The bacteria is picked up and transferred from tree to tree by insects and rain. The disease overwinters in cankers, and produces an infectious ooze in spring. It is a widespread, highly infectious bacterial disease ( Erwinia amylovora) found on apples, pears and other members of the rosaceae family. Post bloom maintain Badge on all summer sprays.įireblight (or fire blight) is perhaps the most heartbreakingly destructive of the apple diseases. As long as you have bloom, keep the Strep on. Cueva and Badge are both soft copper sprays that can be sprayed throughout the season.Īt silver tip through 1/2 green tip apply Kocide. If you know that fireblight is an issue in your area, you should consider applications of copper fungicide spray throughout the growing season as a preventative measure. Time is of the essence! Cut out any visible strikes, about a foot into healthy wood, clean your blades with alcohol between cuts, and remove diseased material from the growing area. During the growing season, trees should be regularly inspected for signs of infection. Cankers from infections during the previous season should be removed during winter pruning. This deprives the disease of one of its main points of entry and gives the tree a chance to grow large enough to survive any later infection. You can improve your tree's chances against fireblight by removing bloom when the tree is young. If you have your heart set on a susceptible variety we understand completely. The majority of heirloom apple varieties are susceptible, while many modern cultivars have been developed for resistance.
APPLE TREE FIRE BLIGHT TREATMENT SERIES
Wilted shoots well-defined areas of burnt-looking, dead foliage or bark sticky amber ooze.įireblight on rootstock can be prevented by planting resistant rootstocks (the Geneva series for apples) and tree varieties. Fireblight (or fire blight) is perhaps the most heartbreakingly destructive of the apple diseases.
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