Systemic Tree Implants

Systemic Implants

by

Bud Franklin

October 30, 2003

The professional tree industry is continuously searching for more effective means of treating trees with nutritional and pest problems. There are numerous methods which can be employed to deliver nutrients and pesticides to plant material and this article’s intent is to discuss those and briefly outline advantages and disadvantages of each.

Plant Nutrients
A brief discussion of how plants take up nutrients is a good place to start. Nutrients such as hydrogen, oxygen and carbon (as in CO2) are present in the atmosphere and the plant absorbs these in relatively large quantities and under normal conditions it is not necessary to further amend these. Macro nutrients, nitrogen, phosphorus, potassium, calcium, sulfur and magnesium are also used in relatively large quantities but are absorbed via the root system. Nutrients referred to as micro-nutrients, iron, zinc, manganese, copper, boron, chloride, and molybdenum, are used in smaller quantities and are also absorbed by the root system. All of these nutrients are necessary for healthy plant growth and they are only categorized to distinguish the relative amounts used by the plant. If any of these nutrients are lacking, out of balance, or are not in the appropriate form the plant can utilize, the plant will experience negative consequences. Under normal growing conditions root hairs on the roots absorb water and dissolved nutrients. Many factors can have an effect on this very important process. To mention a few, the root hairs must be present and functioning, nutrients (macro and micro) must not only be present but also in a soluble form, the soil or growth medium must have the proper characteristics to release the nutrients (cation exchange capacity, correct pH, functioning bio flora) and of course the correct water to air ratio in the soil.

Supplemental Nutrients
There are basically three methods to supplement nutrients. These are soil applied, foliar applied or implants and injection. Soil applied nutrients can be applied by dry fertilizer applications to the surface or liquid applications via root feeders or soil drenches. This is probably the most common approach to addressing nutrient deficiency problems and if it is done properly and periodically (two to three times a year) one can expect to achieve the desired results. There are, however, some areas of concern. First, with any soil application there can be an extended period of time before results can be observed. This is due to all the interactions that must take place between the soil, the nutrient, and external environmental factors before the plant can benefit from the application. Secondly, when using this approach it is necessary to use more material than the plant needs because much of what is applied is either ultimately tied up in the soil or leached below the root zone. Additionally, many synthetic fertilizers are formulated as a salt which over the long term can have a negative impact on soil structure and chemistry as well as plant growth. Soil applications are the only way to address issues in which you are trying to correct adverse soil conditions such as high acidity or alkalinity. Foliar applied nutrients have the advantage of quick response time but the disadvantages of short duration and the difficulty of treating large trees. Additionally, any type of foliar application of nutrient or pesticide has substantial environmental aspects. Drift to non-target plants and animals is a common problem. In the case of nutrient foliar applications this is not normally a concern but it should always be a consideration. However, drift from foliar applications of pesticides can have a major negative impact on non target plants, wildlife and domestic animals. When using this approach it is always extremely important to consider volatility, temperature, wind speed and direction as well a complete evaluation of all non-target organisms in the immediate area which may be exposed to overspray and drift.

Systemic Implanting
Systemic implanting is a method of nutrient application which addresses some of the issues with soil and foliar applications. First, the results are observed within weeks of the application. This is due to the fact the nutrient is implanted directly into the vascular tissue of the plant and is immediately available. Because of the vascular placement, systemic implants are an excellent way to apply nutrient when a plant is in a stress situation such as drought, damage from weather, construction, confined planters, fire or other external factors. Secondly, it is not unusual to control the deficiency for periods of two to three years. Thirdly, it is an environmentally safe way to apply nutrient because of the very small amounts of material needed to correct the problem and the closed system of application which has no negative impact on the soil or atmospheric environment. It is easy to apply and cost effective when you factor the length of control. Systemic implants can also be used to control insect infestations in most ornamental trees. Acecap 97 is a systemic implant containing Acephate, a non-restricted use broad spectrum insecticide, which is easy to use and requires no specialized application equipment or protective clothing. Non-target organisms, people, plants, wildlife and domestic animals are not endangered by this application technique when used according to the label.

Large ornamental trees are a priceless element to our urban and rural landscapes. Their value cannot be expressed in dollars. Unfortunately, there are conditions, sometimes created by nature and sometimes created by humans, that can put these priceless plants at risk. If such an occasion should occur systemic implants offer a unique therapy to return your trees to a healthy and vigorous state. When properly used, you can cure stressed and injured trees in the shortest amount of time, affordably and in an environmentally sound manner.