THE NATURAL REQUIREMENTS OF TREES should be well understood to secure their survival and healthy growth after transplanting. Even the most protected and cared for tree in the nursery suffers a growth shock, temporary or permanent, immediately after planting, depending on the quality of care provided between lifting and planting.
Forest deciduous trees used for transplanting in urban and rural settings suffer most because they undergo serious distortions contradicting their characteristics. Their roots are subjected to stress from the time of lifting, transporting and storing, and then the transplants are often planted too shallowly and too loosely. Finally, the importance of timely crown control to substitute the natural loss of their branches, as normally occurring in the forest, is ignored. If trees are expected to flourish, utmost care in all aspects of tree planting must be pursued to cushion the shock of transfer from a protected environment in the nursery (or forest) to an isolated one in the street or open field.
Tree size is often accepted as an indication of high quality. However, bigger is not necessarily better: The prospects of survival and vigorous growth could be often secured simply by planting smaller trees with temporary protection, as opposed to larger trees planted at higher cost and higher vulnerability to failure. It is not surprising that the average life span of urban trees is often shorter than expected.
The most hostile effect on the survival and initial growth of transplants should be attributed to shallow planting: It keeps the primary roots - the essence of root regeneration - too close to the soil surface, making them vulnerable to rapid drying. A dry planting hole, not pre-watered, compounds the effect of drying. In addition, trees which have been exposed to heat and wind during conventional practices of lifting, transporting and storing, suffer accelerated drying at planting. Thus, trees suffer a transplanting shock, often irreversible, and they die. At best, weakened transplants may hang on for several years, depending on the weather conditions or watering procedures, but, finally, succumb under exhaustion. Conventional guidelines do not satisfy requirements for recovery: The time span between lifting and transporting, and during storage, often lasts several days, and watering is often late or absent, accelerating drying and decline.
The conventional fear of drowning, when planted too deep in soil of poor drainage for prolonged periods of time, may be correct, but does not justify to invite factors which counteract survival and vigorous growth, such as shallow planting. Drainage should be an engineering task relatively easy to solve, while physiological disturbances are difficult to divert damage to transplants done by shallow planting.
Watering as a "quick fix," as often practiced following a drought period, will be of little benefit to already weakened roots which have been continuously exposed to surface drying. As reasoned in this text, planting at a greater depth, where soil moisture is more readily available to the roots, makes watering less urgent during drought periods and saves cost.
Planting trees loosely is a conventional practice needing serious reassessment. Trees in nature flourish well in undisturbed, firm soil, of adequate depth, unlike boulevard trees in insufficiently firmed soil. It does not minimize aeration to a point of suffocation. Well-tamped soil around and over a rootball will prevent air easy access to the roots enhancing drying.
There is a great need to make the tree producers, planters and consumers aware of tree care as for a homeowner to care for the house. If done routinely, it may save costly repairs, and the trees will last longer for our benefit and enjoyment.
This guide points out the misconceptions and errors in the current conventional planting practices and recommends measures that should minimize, even avoid, planting failures. The importance of moisture retention, depth of planting, soil covering and crown control are the primary subjects. A special chapter is devoted to roadside plantings for controlling the effect of wind and snow. Photographs with detailed captions should be eyeopeners by themselves.
Those who wish to enrich their knowledge with unorthodox, down-to-earth facts about tree planting and care should find this guide invigorating and useful.
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Tree Services Magazine