Dear Master Gardener,We have planted a blue birch tree in our front yard two summers ago, but lately it hasn’t been doing very well (since spring). Many of its needles are brown, although the top of the tree is nice and healthy. The tree is in the sun, and the type of soil isn’t that great – one of our neighbours who enjoys gardening noticed that when we planted the tree, we didn’t dig the hole big enough. We also didn’t add fertilizer. We went to Sheridan (where we bought the tree) and they gave us some treatment (fertilizer and something to revitalize it), but it didn’t seem to work. I’m attaching a picture, let me know if you need more from another angle. Thank you for your help,Needle discolouration can be a sign of either a physiological or biological disease. Colorado blue spruce (Picea pungens) can be infected with a needlecast disease caused by the fungus Rhizosphaera kalkhoffii. This fungal infection is most common on young trees. The Rhizosphaera fungus infects needles on the lower branches first and gradually progresses up the tree. Although needles on the new growth become infected in May and June, symptoms are not visible until late fall or the following spring, when infected needles turn purple to brown and begin to drop. From your photo it appears as if the spruce tree is planted close to a main road. Blue spruce are very susceptible to salt spray. “Salt water spray from roads will cause the needles to brown from the tips downward. Sprayed needles shed and the branches become barren and die. Salt spray damage, is restricted to only those parts of the tree actually sprayed. Such damage is more severe on the side closest to the road and to those branches above snow level. Browning becomes evident in late winter and intensifies with time. Salt injury can predispose trees to drought or cold-temperature injury.” www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex4144