subject: Tree Care - Routine Gardening Tasks That Can Damage Your Trees [print this page] Tree Care - Routine Gardening Tasks That Can Damage Your Trees
No other element comes remotely close to a tree's power to move and inspire and nothing in the garden is likely to live and last as long. Trees also take a long time to grow - some can take a few generations to realize their full potential, while even the fastest growing species needs at least five or six years before beginning to "perform". It is when the full potential of a tree is considered that the gardener, amateur and professional alike, has to stop and think not only about how they are caring for the tree itself, but also about the other gardening tasks that they are carrying out in proximity to it.
What exactly is meant by proximity to a tree? Being close extends well beyond the first three or four meters from the trunk. As a rough guide, it's possible to estimate that the roots extend to a horizontal distance about twice the height of the tree. This means that in some cases they can extend over ten meters beyond the tips of the branches and foliage. As any damage caused to the roots of the tree is liable to seriously affect its future growth and development, it follows that the "danger zone" should be considered as the estimated radius from the trunk to the tip of the roots.
In what way then can the garden trees be unintentionally damaged?
*Digging is the major culprit. It should be remembered that the most active roots, those responsible for the majority of water and nutrient intake, grow more or less parallel to the ground to a depth of some 10-30 cm from the soil's surface. So tasks like planting are liable to be highly problematical, if the digging involved results in severing many root parts. It could affect the supply of water and nutrients to the plant as a whole. Furthermore, any wound, above ground and especially below it, is a prime source of fungal and bacterial infection.
*Soil compacted by heavy foot traffic or machinery will reduce the amount of oxygen in the root zone. Remember that the constant passing of vehicles five or six meters from the trunk will be detrimental to the tree.
*Tree roots can absorb residues of herbicides previously sprayed on the ground. The biggest danger comes from the pre-emergent weed killers belonging to the Simazine group. A tree located at the bottom of a trough is particularly vulnerable as the Simazine is easily leached out of sandy soils and can collect in a depression.
*The habit of raking leaves around the trees is also undesirable. It may not compare in gravity to the previous examples, but nonetheless, habitual raking will in time deplete the top soil of its fertility, as soil will inevitably be raked away together with the leaves. The latter of course are best left on the ground as natural organic mulch, where they will eventually decompose to humus.
*Pruning is of course the main source of long term damage to trees. Both quantity and quality play a part here. The more limbs and branches removed at any one time, the more the energy level of the plants is affected. The quality or otherwise of the pruning cuts, determines the extent to which the wounds will heal, and infection avoided.
The tree is such an imposing, massive thing that some people see it as impregnable. Despite its size and splendor it would be more advisable to look on your garden tree as a big baby. Precious, delicate and vulnerable!
About the author - Jonathan Ya'akobi.
I've been gardening in a professional capacity since 1984.
I am the former head gardener of the Jerusalem Botanical Garden, but now concentrate on building gardens for private home owners.
I also teach horticulture to students on training courses.
I'd love to share my knowledge and experience with you.
So you're welcome to visit me on http://www.dryclimategardening.com