Pine disease

Question: I noticed that our swiss pillar pine has these white spots on all of the branches on the bottom third of the tree. They are not present on any of this year's growth. We've had the tree for about 4 years and this is the first that I've noticed it. What should I do?

responder: Paul W. U of M Extension Master Gardener Dakota County Replied July 02, 2023, 2:04 PM EDT
response: Looks like Pine Needle Rust.  Pine needle rust | UMN Extension

responder: The Question Asker Replied July 02, 2023, 3:46 PM EDT
response: Thank you for your response.Since I messaged initially, I've been reading more about armored scale on the umn website as a possibility given that the white areas are quite flat to the needle and done excrete anything.If this is armored scale:1. Should I remove the affected branches?2. Should I treat it systemically?3. Will this continue to spread throughout the tree given that 1/3 is already affected4. Do I need to take action now?Thank you again for your help- I greatly appreciate it as this tree is a focal point in our landscape.Sincerely,CaseyOn Sun, Jul 2, 2023, 1:04 PM Ask Extension <<personal data hidden>> wrote:

responder: Paul W. U of M Extension Master Gardener Dakota County Replied July 03, 2023, 10:42 AM EDT
response: Here is an article on Pine Needle Scale, but maybe you have seen it already. It does address treatment. PineNeedleScale (umn.edu) You should treat it now, because the scale will spread.   You can use both a topical treatment and a systemic treatment. The solution is going to be multi year.  You say the tree is important to your landscape and calling a tree care specialist might be in order, particularly if branches are to be removed and you may have to remove the bottom branches.

responder: The Question Asker Replied July 03, 2023, 2:30 PM EDT
response: Thanks for your response.Do you have any resources if where to buy those products? Especially, the dinoteferon.Do the treatments need to be done urgently or is it something that can be done sometime this summer/fall? Thanks,CaseyOn Mon, Jul 3, 2023, 9:42 AM Ask Extension <<personal data hidden>> wrote:

responder: Paul W. U of M Extension Master Gardener Dakota County Replied July 04, 2023, 8:35 AM EDT
response: I suggest that you "Google" each of the systemics for their trade names. Dinotefuran is trade name "Safari" and it is available on Amazon. It is not cheap, but is really effective. It is a neonicotinoid.

responder: The Question Asker Replied July 10, 2023, 12:35 AM EDT
response: Thanks for that additional info!Currently, my questions are:1. At what point should I treat it systemically... Now, this fall, next spring?2. Some literature mentions to wait until the plants are done flowering before treating due to pollinator harm. I'm assuming the close proximity perennials such as cone flower, speedwell, etc will be treated and they are currently blooming... Is this an issue?3. Will someone from the local Extension agency be able to actually come out and look at the tree or can I send in a specimen to 100% verify the pest before treating?4. I was told by a local nurseryman to try cleaning off the needles manually with alcohol. I have done this a little and they do come off easier. Would horticulture oil be better? Should I go back and do that still?Thanks again,CaseyOn Tue, Jul 4, 2023, 7:35 AM Ask Extension <<personal data hidden>> wrote:

responder: Paul W. U of M Extension Master Gardener Dakota County Replied July 10, 2023, 12:09 PM EDT
response: 1. You should treat the tree now. 2. The concern is drift from spraying the tree. I would apply the systemic with a squirt bottle on an absolutely still day. 3. Call the local Extension office and see if they will pay a visit. Take a sample to the local nursery or to your city forester (if they have one) or call a local arborist. 4. Hand removal works, but it will be very time consuming. Horticultural oil will work, but you need to be sure you cover the scale so they will suffocate. You can remove them by hand, use horticultural oil, or a systemic or any combination of the three.