What is killing my apple trees?

Question: I have an apple orchard and recently my trees have started to die. Attached are several photos from one of my apple trees. Whatever is killing them removes the bark and drills holes throughout. Also note the pattern of the marks it makes in the wood.

responder: An Ask Extension Expert Replied May 16, 2024, 10:56 PM EDT
response: Hello,  Can you please send me clear, close-up images of the trunk of an apple tree where the bark has fallen off? These images will hopefully show the distinct pattern of marks and holes. Thank you!   THESE MIGHT BE CAMBIUM MINERS Cambium miners are typically insects that burrow between the bark and the wood, disrupting the flow of nutrients and water. Here’s a general guide to diagnosing cambium miners:   Define the Problem: Look for irregular patterns or disruptions on the tree bark that may indicate the presence of cambium miners.   Look for Patterns: Cambium miners often leave distinctive trails or galleries on the bark, which can help identify them.   Determine Causes: Check for small holes, sawdust-like frass, or the insects themselves, which are signs of cambium miner activity.  Please send me clear, close-up images of the trunk of an apple tree where the bark has fallen off. Then, I will tell you the next step to get a precise identification. Thank You!

responder: The Question Asker Replied June 24, 2024, 10:46 AM EDT
response: Hi, I see that this case has been closed; however, I didn't hear back from you after I sent the other pictures. If they are cambium miners, what can I do about it? Thank you   Frank

responder: An Ask Extension Expert Replied June 26, 2024, 12:11 PM EDT
response: I have never seen cambium miner in apple. However, if your trees are older, it is possible... have you seen larvae in the tree? How about sawdust?  Any more pictures might help. Thank you.

responder: The Question Asker Replied July 05, 2024, 4:53 PM EDT
response: I have not seen any sawdust or larvae. They are older trees that this is happening to. All of the pictures look similar so I don't know what other type of photos you would need to help with this. It is clearly spreading to my other trees (I have an apple orchard) and need to get a handle on this.  If you could let me know more specifically what type of pictures to take, I could definitely send you more. Thank you. FranK      On Friday, July 5, 2024 at 04:47:59 PM EDT, Sue Destrampe <<personal data hidden>> wrote:        On Wednesday, June 26, 2024 at 12:12:05 PM EDT, Ask Extension <<personal data hidden>> wrote:

responder: The Question Asker Replied July 05, 2024, 4:53 PM EDT
response: On Wednesday, June 26, 2024 at 12:12:05 PM EDT, Ask Extension <<personal data hidden>> wrote:

responder: An Ask Extension Expert Replied July 10, 2024, 12:03 PM EDT
response: Hi again, Frank. I really think you do have borers in your tree. We have lots of different species, and I am not sure which of the species is causing your issue. The problem is that they are so hard to control because they are inside the wood of the tree. Our commercial growers spray pesticides on the trunk, but my guess is that you do not have a license to use materials that will kill them.... is there a way you can wrap your trunks in burlap? To provide a physical barrier to the beetles? This might work... Nikki

responder: The Question Asker Replied July 15, 2024, 12:42 PM EDT
response: I will try that. Thank you for your help.

responder: The Question Asker Replied September 04, 2024, 12:07 PM EDT
response: I received information saying to put burlap around the base of the trees. I was also told there was a spray that a professional would need to get rid of them. Sleemans, a local greenhouse, said they could get someone to do it if they knew what spray was needed. Could you send me that information, or would I need to get their contact information for you? I am losing a lot of trees to this.Thanks,Frank  On Friday, July 5, 2024 at 04:48:54 PM EDT, Sue Destrampe wrote:     I have not seen any sawdust or larvae. They are older trees that this is happening to. All of the pictures look similar so I don't know what other type of photos you would need to help with this. It is clearly spreading to my other trees (I have an apple orchard) and need to get a handle on this. If you could let me know more specifically what type of pictures to take, I could definitely send you more.Thank you.FranK On Friday, July 5, 2024 at 04:47:59 PM EDT, Sue Destrampe wrote:       On Wednesday, June 26, 2024 at 12:12:05 PM EDT, Ask Extension wrote:

responder: An Ask Extension Expert Replied September 04, 2024, 2:21 PM EDT
response: Hello Frank. I am sorry to say that I am not sure trunk sprays will work. If your local company can do a trunk injection, that may work to kill insects that are already inside of your tree. How many trees have died as a result of this symptom? Do you see any dead limbs or leaves, and if you pull up trees, what do your roots look like? The trunks and bark from the pictures look very dried out. I am wondering if moisture or other pieces are at play in addition to your insect damage. Where are you located?  Nikki Rothwell

responder: The Question Asker Replied September 07, 2024, 6:04 PM EDT
response: I am located in Houghton, and I have roughly 1000 apple trees. Last year I lost a couple and so far this year roughly 10 more have died. I am concerned because I see multiple other trees with dead limbs and upon inspection the bark has fallen off and I can see the pinholes where the bugs have burrowed inside. I have not pulled up any of the trees to see the roots. I do not water the trees because I have so many, but I never have, and I just noticed this problem a year ago. I am afraid it will keep spreading and kill all my trees.  On Wednesday, September 4, 2024 at 02:21:09 PM EDT, Ask Extension wrote:

responder: An Ask Extension Expert Replied September 09, 2024, 9:30 AM EDT
response: Hello. I think I have spoken to you in the past, and I am not sure of what is going on with your trees. One thing would be is to pull up a tree and take pictures of the roots and send them to me. I see those borers, but we do not usually see those pests kill a tree. I am wondering if something is going on below the ground that we cannot see. I am thinking voles... Please pull up a tree and take pictures. I think this will help us get to the bottom of this issue.  Nikki

responder: The Question Asker Replied September 18, 2024, 5:17 PM EDT
response: On Monday, September 9, 2024 at 09:30:45 AM EDT, Ask Extension wrote:

responder: The Question Asker Replied September 18, 2024, 5:17 PM EDT
response: The first photos were of the roots and the last of the hole. On Monday, September 9, 2024 at 09:30:45 AM EDT, Ask Extension wrote:

responder: An Ask Extension Expert Replied September 19, 2024, 12:35 PM EDT
response: Hello. Thank you for the new pictures. I think these trees are dying at the soil line. I think that this is winter damage. I see that you are up in Houghton, and I think this is the problem. How was your snow cover last winter or the winter before? Sometimes we can see trees go down with winter injury one to two years after the cold event.  Did you take pictures of many trees or one?  Nikki

responder: The Question Asker Replied September 19, 2024, 1:41 PM EDT
response: There were three trees that I took pics of. Last year we didn’t get very much snow at all. What is causing the bugs in there? On Thursday, September 19, 2024 at 12:35:56 PM EDT, Ask Extension wrote:

responder: An Ask Extension Expert Replied September 20, 2024, 12:05 PM EDT
response: The bugs are minor, I believe. They are cambium borers, and we rarely see them damage trees enough to kill them. I suggested burlap to cover trunks to prevent them from boring because it is hard to get insecticide into the trunks--even commercial growers struggle with borers. My thing would be to give them foliar nitrogen applications as the leaves start to fall from the trees. They will take these nutrients back to the roots to store for the winter, and hopefully they will push better in the spring. Make sure the nitrogen source is for foliar use otherwise it will burn the tree, which is the last thing you need! Good luck. Let's hope for snow cover this winter.  Perhaps you can email me directly if you have further questions: <personal data hidden>