Planting Trees-Select the right trees for the right planting site. Do not plant trees that will grow big: in small spaces, under power lines, or close to buildings. Do not buy trees that have cankers, wounds, included bark, cracks, flush cuts, poor form, girdling roots. Do not buy trees that have been in containers so long that roots are spiraling. Trees need to be planted at the proper depth and never planted too deeply. A really good time to plant trees in the PNW is in the fall and early spring.
Mulching Trees- Trees benefit from not having grass around their trunk and even under their canopy, this allows more water and nutrients to ge to the trees roots. Mulching is great but don't over mulch. The best mulch for a tree is its own leaves or needles. Provide your tree with a tree ring of wood chip mulch out to the dripline, or edge of the canopy, and avoid having grass grow up to the trunk. This can also prevent unnecessary lawn mower or weed-whacker damage to the tree.
Watering Trees-A newly planted tree needs supplemental watering for 12-18 months after its planted. It is better to water deeply but infrequently. In general, soil should be allowed to dry out between waterings. If it has not rained for 4-6 weeks then offer water even to established trees and shrubs.
When the right plant is planted in the right place there is much benefit with little maintenance.
Start Pruning early.-Prune early in the life of the tree to establish the framework for the kind of tree you want. The framework is the basic woody design of the tress that determines the shape or architecture of the tree.
Offer proper care to old trees, respecting their dignity. Don't bury the root crown with soil or mulch. Don't cut large roots or change the grade. Instead, provide a wood chip mulched tree ring, avoid excavation activities in the critical root zone, especially within the dripline. and plant companion plantings of suitable shrubs, ferns, and flowers.