Thanks for the questions. In general, soils in Minnesota are high in phosphorus. Applying a fertilizer with a middle number of anything above zero adds to the situation. So you should not apply any fertilizer with phosphorus! Compost and manure are also sources of phosphorus, so avoid applying either of those as well. The only way to reduce phosphorus in the soil is to grow plants. As they grow and take up phosphorus, which is a slow process perhaps taking several years.  Typically, a tree growing in a lawn area does not need any additional fertilizer beyond what you may be (or may not) apply to the lawn.

I suspect that the browning needles are due to winter desiccation. Be sure to water all trees throughout the growing season right up until the ground freezes in November. Here is a link to more information on the importance of watering trees: https://extension.umn.edu/planting-and-growing-guides/watering-established-trees-and-shrubs

Paul -Tree Care Advisor volunteer