Whether trees are being planted for reforestation, ornament, shade, or fruit, the first step is selecting the species to be grown. The choice depends on such factors as the characteristics of the soil, the location of the site, and drainage. For example, sycamore and cottonwood trees will not grow on dry exposed slopes or ridges, or in fields with a thin topsoil over a heavy compact subsoil. Walnut trees will not grow in swampy places, and jack pines grow especially well on loose sandy soils with good drainage. A good rule of thumb is to plant native trees–trees that have demonstrated their ability to thrive in the local environment without harming other local species. The hole for a seedling should be deep enough to hold the fully expanded root system of the seedling. Larger plants should be placed in a hole 60 cm (2 ft) deep with a diameter 60 cm greater than that of the ball of the roots. In poor soil the hole should be 1.8 m (6 ft) wide and 60 cm deep for a 2.5-m (8-ft) tree, and proportionately wider for taller trees. After the tree is placed in the hole, the soil should be firmly pressed around the roots, and the ground should be thoroughly soaked with water. Mixing bone meal or well-rotted manure into the soil will help the tree become established quickly. Most deciduous trees should be planted in the fall when they are not growing, but evergreens are usually planted in the spring, at the beginning or middle of their period of vigorous growth. Watering Trees After planting, the soil around a tree should be kept moist, but not soaked. If artificial watering is not practical, a layer of mulch 7 to 15 cm (3 to 6 in) deep should be placed around the tree to conserve moisture and to discourage the growth of weeds. Because a transplanted tree does not adequately absorb water through its damaged roots, it is important to prevent water loss from the plant by pruning top limbs to limit transpiration. Fertilizing Trees In good soils it is less important to fertilize than in poor soils. However, all trees grow better and faster and are less likely to become diseased if fertilizer is supplied in the proper amounts. This may be done most easily by placing a large handful of fertilizer in holes made by a crowbar at the edge of the spread of the tree’s limbs. The holes should be about 60 cm (2 ft) deep and about 5 cm (2 in) in diameter, and they should be spaced about 90 cm (3 ft) apart. After the fertilizer has been introduced, the holes should be filled in with soil. Organic fertilizers such as manure and mulch are preferable to chemicals that may replace or destroy natural organisms in the soil. Pruning Trees Pruning of ornamental trees maintains the form of the tree, removes weak or sickly branches, and rejuvenates old or unhealthy plants. If performed during a period of vigorous growth, pruning often also results in an increased production of flowers. In pruning, cuts are made just above the buds that point in the direction branches are desired. When large branches are removed, the cut should be made close to the trunk, and then covered for a time. Always be careful when pruning trees. More information about Tree Care right here