Hi,
I need help with a diagnosis of what is afflicting two potted (5 gallon) columnar apple trees that were given to me 7-6-07.
I am worried that it is a disease that can spread to my three very healthy apple trees, which are still in pots waiting to be planted.
Is there a minimum safe quarantine distance I should keep them at in the meantime?
here is another photo
and the last one
Apple Scab
Whether it will spread depends on what varieties your other trees are. Some are immune, others are quite susceptible. If you post the names of your other trees, I'll look up whether they are immune or not since I haven't posted my database to PlantFiles completely yet.
Treatment involves spraying with fungicides, such as captan, on a schedule throughout the year. Your county extension agent should be able to provide a spray schedule based upon your climate or you can follow the one that WSU has posted http://cru.cahe.wsu.edu/CEPublications/eb0846/eb0846.html
Apple Scab is not fatal right away, so you can start preventative sprays starting early next spring. Practice good tree management to keep the disease in check by cleaning up fallen fruit and branches in the fall and destroying them (preferably by burning, not composting them)
Hi Amandaemily,
Thanks so much for helping me with this!
My other trees are North Pole, Liberty and Gold Rush.
I so appreciate your help!
The North Pole being a McIntosh is susceptible to scab, the other two are immune.
There is unfortunately nothing that can be done this year for the scab, but it can be controlled next year with fungicides.
Any leaves that fall from your new trees, pick them up and remove them from your property ASAP to keep scab from spreading since it overwinters on fallen leaves. The North Pole will only be susceptible to infection next spring when it first leafs out and blooms, but good sanitation is a good habit to get into.
Hi Amanda,
Thanks again so much for the information - nice to know that two of our trees are immune!
People like you are what makes Dave's garden such a great place!
