Apple trees are dying off and experts don't know why
Experts say the upcoming growing season may be difficult.
Apple trees are dying in large numbers in parts of Canada and the U.S., and experts aren't sure if the culprit is extreme weather, bacteria, or a combination of things.
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The condition -- which is called Rapid Apple Decline (RAD) -- is first identified on apple trees by leaves that curl and turn yellow, brown or red. Within two weeks, the tree usually dies.
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Kari Peter, a plant pathologist at Pennsylvania State University who studies fruit tree diseases, told Good Fruit Grower that one grower has lost 20 per cent of his orchard due to RAD, with more trees dying every year.
A Plos One paper published in March suspected several environmental factors could be at play, including weather, soil, bacteria and fungi.
Researchers tested several trees, but could not find a common factor among the affected plants.
The paper believes declining moisture levels in roots combined with extreme weather might cause RAD, but "cannot clearly rule out the involvement of other factors".
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Experts suspect the upcoming growing season may be a challenge, with no treatment options available for RAD-affected trees.
The condition has been observed in the central, northeastern and northwestern U.S.
In Canada, it has been reported in Ontario.