Not commonly used for landscaping and ornamental trees. Primarily used for reforestation, land rehabilitation, and other conservation project planting stock. Some species that are difficult to grow and harvest in the field can be offered as potted stock. Examples include aspen and Rocky Mountain juniper. Want a mixture that offers a balance between good drainage and water retention, and adequate air space.
Air space is probably the single most critical factor in a potting mix, then water retention.
Fertility can be controlled by the owner. A tree bark component is sometimes used, especially in the Northwest. The time it takes to grow a tree to harvest varies with species, desired size, site, soil, growing season, maintenance and watering, and other factors. Growth rates at nurseries located at higher elevations where the growing season is shorter would probably be slower than those at lower elevations. If there is a nursery in your area, check with it to get an idea how long it takes to grow a marketable product.