A Trees Need For Nutrients

If you own trees or plan on planting trees – understanding their need for nutrients is vital. All trees require the right amount of nutrients to live and thrive. If even one or more of these nutrients are deficient in the soil, the tree will not reach its full landscape potential, will be more susceptible to disease and insect problems, and will have a shorter life than a similar, well-fertilized tree.

To understand the nutrients trees need, one first looks out how these nutrients are divided into two groups: macronutrients and micronutrients, based upon the quantity necessary for growth. Macronutrients are required by plants in larger quantities than micronutrients. Macronutrients include nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and sulfur (S).

Micronutrients, which are required in very small amounts, include iron (Fe), manganese (Mn), zinc (Zn), copper (Cu), boron (B), chlorine (Cl), and molybdenum (Mo).

Many fertilizers are designed with the right amount of nutrients in the right proportions, which helps to take the guesswork out of fertilizing. All fertilizer labels indicate the amount of nitrogen, phosphorus, and potassium contained in the product by percent. These labels also indicate the weight of these nutrients per 100 pounds of product. For example, 100 pounds of a fertilizer marked 10-8-6 contains 10 pounds of nitrogen in various forms [eg. ammonium (NH4) or nitrate (NO3)], 8 pounds of phosphate expressed as P2O5, and 6 pounds of potash expressed as K2O. Fertilizers containing N, P, and K, such as 9-18-9 and 20-20-20, are referred to as “complete fertilizers”.

If you are trying to stay completely organic, fertilizers are offered in this form as well. Organic fertilizers take time to break down and release nutrients more slowly.

To determine when to fertilize or how much, take into consideration your environment, whether your trees have been under stress due to low moisture, whether they have been damaged physically. Competition by nearby turf and trees can cause stress on your trees. And if you have just planted your tree, it is important to keep weeds away from their bases to avoid excess stress.

Another way to determine whether your tree needs fertilized is to do a soils test by taking a sample. Ideally, a soil sample should be taken before trees are planted. Additional samples can be taken every 3 to 5 years thereafter to determine whether any nutrients are lacking. A soil test kit may be obtained from your county extension service.

In the absence of a soil test, the best indicator of the need for additional fertilization of established trees is shoot growth. If new shoot growth (growth occurring in the present year) is in excess of 6 inches, then fertilization is probably unnecessary. If shoot growth is between 2 and 6 inches then fertilizer may be applied.

Foliage color is another indicator of the need for fertilization. Yellow or “off-color” leaves may indicate the need for fertilization as these symptoms generally occur on trees, which are not taking up enough of one or more required nutrient. Always remember, however, that apparently “off-color” leaves are normal for certain plants such as ‘Sunburst’ Honeylocust and some maple and ash trees in the fall.

A final indicator of the need for fertilization is the history of the yard. Trees in yards that are fertilized for turf on a regular basis rarely need to have supplemental fertilizer applied. Supplemental fertilizer should only be considered if shoot growth is less than two inches, or if a soil test reveals a specific nutrient deficiency.

When should you fertilize? Most trees experience a single flush of growth during spring followed by slower growth throughout the summer and fall. Because of this single flush of growth, it is desirable to have nutrients available to the tree as this growth is about to occur. The most beneficial time to apply fertilizer is from when the ground is workable in the spring until just before trees start growing in early May. On sandy soils, applications should be split, half in early spring and half in mid- to late May.

If you have trees, put them on a schedule, monitor when you have fertilized and any changes. And remember, it is vital for their healthy growth.

Andrew Johnson is the owner of Central Texas Tree Care, a leading tree service provider in Central Texas (Travis County and surrounding areas) offering services such as pruning and removals, cabling and bracing as well as arborist reports, diagnostics, pest management, fertilization and Austin tree service trusts. For more information please visit http://www.centraltexastreecare.com.

Caring For Your Mature Trees

Trees can live for years, even hundreds of years. The oak or walnut can live as long as 200 to 300 years. This means these trees could be witness to up three or four generations of people. A tree of this age has great value and in that also requires great care.

With a little preventative care, your trees can last as long as this. And remember that curing a problem once it develops is much more difficult, time-consuming and costly than preventing one. So isn’t it worthwhile to give your trees regular maintenance to ensure that they are able to offer enjoyment and value for generations to come? If so, lets look at what kind of care a tree needs so that it can grow old graciously.

1. Tree Inspection – To start with your tree’s personal care, you should first have an inspection by a certified professional arborist. Tree inspection is an evaluation tool that will help determine whether the tree is in good or bad health or on the brink of anything disastrous. By providing regular inspections of your trees at least once a year, you can prevent or reduce the severity of future disease, insect, and environmental problems. A professional will evaluate your mature tree for four characteristics of tree vigor: new leaves or buds, leaf size, twig growth, and absence of crown dieback (gradual death of the upper part of the tree).

Any abnormalities found during these inspections, including insect activity and spotted, deformed, discolored, or dead leaves and twigs, will be noted and watched closely. The Arborist or other tree care professional will be able to determine the best solution for the tree’s condition.

2. Mulching - Mulching cools and contains moisture around the tree, which in turn can reduce environmental stress. Mulch can also prevent mechanical damage by keeping machines such as lawn mowers and string trimmers away from the tree’s base.

Mulch should be placed 2 to 4 inches deep around the tree and cover the entire root system, which may be as far as 2 or 3 times the diameter of the branch spread of the tree. If the area and activities happening around the tree do not permit the entire area to be mulched, it is recommended that you mulch as much of the area under the drip line of the tree as possible. When placing mulch, try not to cover the actual trunk of the tree.

3. Fertilization - Trees require certain nutrients (essential elements) to function and grow.
Fertilizing a tree can improve growth; however, if fertilizer is not applied wisely, it may not benefit the tree at all and may even adversely affect the tree. Mature trees making satisfactory growth may not require fertilization. When considering supplemental fertilizer, it is important to know which nutrients are needed and when and how they should be applied.

Soil conditions, especially pH and organic matter content, vary greatly, making the proper selection and use of fertilizer a somewhat complex process. When dealing with a mature tree that provides considerable benefit and value to your landscape, it is worth the time and investment to have the soil tested for nutrient content. Any arborist can arrange to have your soil tested at a soil testing laboratory and can give advice on application rates, timing, and the best blend of fertilizer for each of your trees and other landscape plants.

4. Pruning - Pruning is the most common tree maintenance procedure next to watering. Pruning is often desirable or necessary to remove dead, diseased, or insect-infested branches and to improve tree structure, enhance vigor, or maintain safety. Because each cut has the potential to change the growth of (or cause damage to) a tree, no branch should be removed without a reason.

Removing foliage from a tree has two distinct effects on its growth. Removing leaves reduces photosynthesis and may reduce overall growth. That is why pruning should always be performed sparingly. Over pruning is extremely harmful because without enough leaves, a tree cannot gather and process enough sunlight to survive. However, after pruning, the growth that does occur takes place on fewer shoots, so they tend to grow longer than they would without pruning. Understanding how the tree responds to pruning should assist you when selecting branches for removal.

Maintaining your trees into old age just requires a little patience and care, just like anything. In the end, you will have a beautiful and healthy addition to your landscape and life.

Andrew Johnson is the owner of Central Texas Tree Care, a leading tree service provider in Central Texas (Travis County and surrounding areas) offering services such as pruning and removals, cabling and bracing as well as arborist reports, diagnostics, pest management, fertilization and Austin tree service trusts. For more information please visit http://www.centraltexastreecare.com.