apple disease

Question: I have an orchard of about 40 apples trees.  Have a major problem with different apple diseases. Scab, codling moth and unknown problem, mostly concerning honey crisp variety. I spray with dormant oil in fall and early spring. After blossom petal fall I spray with Bonide Fruit Tree spray about every 3-4 weeks. This is not doing the job. I would like your suggestion on a spray schedule. I try to pick to keep a clean orchard, disposing of all apples that have fallen off trees. A fertilizer recommendation could also be included. The main problem is with honeycrisp as pictures will indicate. I do have problems with scab, in different variety , and codling moth.

responder: An Ask Extension Expert Replied October 28, 2024, 12:54 PM EDT
response: Hello Russell, We are waiting on MSU Extension to publish a drafted home fruit spray guide, but in the meantime I like to suggest this guide from New Hampshire: https://extension.unh.edu/sites/default/files/migrated_unmanaged_files/Resource005256_Rep7402.pdf  A general product like Bonide's fruit spray has limited ability to control every issue, especially on a difficult to manage cultivar like Honeycrisp. There are home spray products that have more specific and effective control than the general product you have been using. Just as important is timing your sprays effectively. You can use a tool like Enviroweather https://enviroweather.msu.edu/ to monitor conditions for specific pests and disease in your area based on weather conditions in addition to following the articles published in-season by our extension staff (for you the Northwest MI reports will be best) https://www.canr.msu.edu/fruit/  If you haven't done a soil test recently you should have one done, which would come with recommendations for fertilization. https://homesoiltest.msu.edu/get-started  Your practice of keeping the orchard free from diseased fruit is one you should continue.

responder: The Question Asker Replied October 30, 2024, 7:55 AM EDT
response: What is causing the damage to my honeycrisp apples? I am not talking about the ones affected by codling moth. Actually just found a worm in one of them. But majority just brown bruising and rotting apples while remaining on tree. On Sun, Oct 27, 2024 at 7:40 AM Ask Extension <<personal data hidden>> wrote:  Dear Russell, Thank you for using Ask Extension. A request for support has been created and a representative will follow-up with you as soon as possible. Questions are usually answered within two business days. You can view this question's progress online. YOUR QUESTION #0158747: apple disease I have an orchard of about 40 apples trees. Have a major problem with different apple diseases. Scab, codling moth and unknown problem, mostly concerning honey crisp variety. I spray with dormant oil in fall and early spring. After blossom petal fall I spray with Bonide Fruit Tree spray about every 3-4 weeks. This is not doing the job. I would like your suggestion on a spray schedule. I try to pick to keep a clean orchard, disposing of all apples that have fallen off trees. A fertilizer recommendation could also be included. The main problem is with honeycrisp as pictures will indicate. I do have problems with scab, in different variety , and codling moth. Ask Extension offers one-to-one expert answers from Cooperative Extension/University staff and volunteers within participating Land-Grant institutions across the United States. If you wish to provide additional comments or information regarding the issue, please login to your account for a complete archive of your prior questions and answers.  This message for informational purposes only. It is not intended to be a substitute for personalized professional advice. For specific local information, contact your local county Cooperative Extension office or other qualified professionals. eXtension Foundation does not recommend or endorse any specific tests, professional services, products, procedures, opinions, or other information that may be mentioned. Reliance on any information provided by eXtension Foundation, employees, suppliers, member universities, or other third parties through eXtension is solely at the user's own risk. All eXtension content and communication is subject to the Terms of Use which may be revised at any time.

responder: An Ask Extension Expert Replied October 30, 2024, 9:44 AM EDT
response: I can't say for sure what is causing the damage. When were the pictures you provided taken? Often those symptoms of browning are generalized responses to damage that can come from a variety of sources.

responder: The Question Asker Replied October 31, 2024, 5:40 PM EDT
response: ABOUT A WEEK AGO On Wed, Oct 30, 2024 at 9:44 AM Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied October 31, 2024, 5:40 PM EDT
response: i WOULD SAY ABOUT 1/2 OF MY hONEYCRISP WERE AFFECTED  On Thu, Oct 31, 2024 at 5:37 PM Russ Fairbanks <<personal data hidden>> wrote:ABOUT A WEEK AGOOn Wed, Oct 30, 2024 at 9:44 AM Ask Extension <<personal data hidden>> wrote:

responder: An Ask Extension Expert Replied October 31, 2024, 6:17 PM EDT
response: Honeycrisp in your region would have been ready to pick in mid to late September. When the fruit is on the tree too long it gets overripe and softens. This leaves it susceptible to various rots, insects, and animals. If you follow the northwest Michigan fruit news articles next year you should be better informed about  harvest dates.

responder: The Question Asker Replied November 02, 2024, 6:50 AM EDT
response: The problem was there in early September On Thu, Oct 31, 2024 at 6:17 PM Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied November 04, 2024, 5:00 AM EST
response: Is spraying neem oil worth the effort in early spring and late fall On Sat, Nov 2, 2024 at 6:46 AM Russ Fairbanks <<personal data hidden>> wrote:The problem was there in early SeptemberOn Thu, Oct 31, 2024 at 6:17 PM Ask Extension <<personal data hidden>> wrote:

responder: Lindsay Brown  Replied November 04, 2024, 10:10 AM EST
response: Hi Russell,  Thanks for reaching out! Honeycrisp are difficult to manage on account of their specific nutritional needs. They must be supported with adequate fertilizers - especially calcium - to help them maintain cell structure integrity. Apples without proper fertilizer applications are more susceptible to infection. I have attached a resource on apple nutrition below. If you are seeing symptoms like this, then I would definitely add more fertilizer in the spring.  Yes, as Derek said, pictures taken later in the season after the issues emerge make it harder to diagnose specific issues. Also, this was just a weird season! Everything was ripe about two weeks ahead of schedule, which could have contributed to your issues. Honeycrisp were ripe in late August/first week of September. The heat and moisture really helped promote pest and disease pressure this year too. If you saw more pest pressure than normal, you are certainly not alone! I can say that the tree fruit spray is most likely not very effective, especially at 3-4 week intervals. They should be treated with fungicides every 7-10 days (or after two inches of rain) from mid March- mid June to fully treat for apple scab. Regarding your neem oil question, oils aren't very effective insectides. If you're having issues with scale insects like San Jose Scale, then oil applications right before bud burst can effectively suffocate the emerging pests. However, it will not be effective against something like codling moth. I would skip fall applications too!  If you are interested in fall orchard clean up, then mowing leaves over, removing fruit and applying urea in the fall can encourage leaf decomposition and reduce overwintering inoculum.  Here's a resource for apple IPM: Apple IPM for Beginners | Cornell Fruit Resources: Tree Fruit. It has more details in it than I can cover here and includes a schedule for treatment timing!  Good luck,

responder: Lindsay Brown  Replied November 04, 2024, 10:10 AM EST
response: Hi Russell,  Thanks for reaching out! Honeycrisp are difficult to manage on account of their specific nutritional needs. They must be supported with adequate fertilizers - especially calcium - to help them maintain cell structure integrity. Apples without proper fertilizer applications are more susceptible to infection. I have attached a resource on apple nutrition below. If you are seeing symptoms like this, then I would definitely add more fertilizer in the spring.  Yes, as Derek said, pictures taken later in the season after the issues emerge make it harder to diagnose specific issues. Also, this was just a weird season! Everything was ripe about two weeks ahead of schedule, which could have contributed to your issues. Honeycrisp were ripe in late August/first week of September. The heat and moisture really helped promote pest and disease pressure this year too. If you saw more pest pressure than normal, you are certainly not alone! I can say that the tree fruit spray is most likely not very effective, especially at 3-4 week intervals. They should be treated with fungicides every 7-10 days (or after two inches of rain) from mid March- mid June to fully treat for apple scab. Regarding your neem oil question, oils aren't very effective insectides. If you're having issues with scale insects like San Jose Scale, then oil applications right before bud burst can effectively suffocate the emerging pests. However, it will not be effective against something like codling moth. I would skip fall applications too!  If you are interested in fall orchard clean up, then mowing leaves over, removing fruit and applying urea in the fall can encourage leaf decomposition and reduce overwintering inoculum.  Here's a resource for apple IPM: Apple IPM for Beginners | Cornell Fruit Resources: Tree Fruit. It has more details in it than I can cover here and includes a schedule for treatment timing!  Good luck,

responder: The Question Asker Replied November 05, 2024, 7:28 AM EST
response: Thanks for the info.  On Mon, Nov 4, 2024 at 10:10 AM Ask Extension <<personal data hidden>> wrote: