Thank you for your question.

Judging from your pictures, it appears that you have Eastern White Pine (Pinus strobus). Besides the brown needles, I am concerned by the possible appearance of blisters (bumps) on the stems of the trees. These are symptoms of White Pine Blister Rust. To deal with this issue, I have two suggestions.

1). Contact a licensed, professional arborist to make an onsite inspection of your trees. Often there is no charge for this. See:

https://extension.umn.edu/planting-and-growing-guides/how-hire-tree-care-professional

2). Then secondly as a check on what this arborist might tell you, submit tree samples to one of the following plant disease diagnosis laboratories. Contact them first before sending in any samples as to what should be submitted:

https://pdc.umn.edu/

https://pddc.wisc.edu/

With respect to your soil analysis, the soil texture is coarse. This is very typical of soils in Anoka County and reflects the fact that your soil is quite sandy with rather poor water retention. You seem to have a fair amount of mulch surrounding the tree. This can impede the flow of water down to the tree roots. I would suggest the removal of the existing mulch and replacing it with fresh mulch to the extent that this new mulch would be about half the amount that is presently around the tree. If there is any fabric covering under the old mulch, remove that completely before adding new mulch. See the following for instructions as to how this might be done:

https://www.maplegrovemn.gov/DocumentCenter/View/1996/How-to-apply-mulch-around-trees-PDF

https://extension.umn.edu/planting-and-growing-guides/watering-newly-planted-trees-and-shrubs

Your soil analysis suggests addition of nutrients in the ratio of 1-0-1. This DOES NOT indicate the soil around the tree is perfect. Essentially the suggestion is to add nitrogen and potash (first and third numbers) and no phosphate (middle number). The relatively high phosphorous level may be due to the amount of mulch you have present. If you reduce this quantity of mulch with fresh material, this will tend to decrease the soil phosphate. In short, I would suggest that you use a 10-10-10 fertilizer. This should be available at all gardening centers. Apply approximately 0.5 pounds of this fertilizer around the base of the pines (do this after new mulch is present) out to approximately 2 feet from the base of the tree. Water this in extremely well. Continue this watering daily for at least two weeks after application. This watering is very important as it will ensure that the fertilizer nutrients reach the root system. See:

https://www.maineforestry.net/fertilizing-trees-and-shrubs

One final suggestion, to prevent you from expending money unnecessarily on fertilizer and additional mulch, have an arborist make an assessment first and get a diagnosis from a plant disease clinic.

Good luck. Please get back to us with any related questions that you might have. Thanks for using our forum