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2007 August LSMP Tree Care: Microinjection Technology: A History08-02-07 | News

Microinjection Technology: A History

Depending on tree size, type, and formulation rate, applications generally vary from 30 seconds to two minutes per caliper inch. With the Arborjet System one may expect to inject three to four 10” inch trees or one to two 60” inch trees in an hour.

Microinjection, the process of injecting trees with pesticides and other chemicals, is a relatively new technology. Although modern microinjection techniques date back to about 40 years ago, today microinjection is a vital aspect of tree care.

In fact, microinjection may be the only way to save many trees from the infestation of several non-native insects like the Emerald ash borer, Asian long-horned beetle and the hemlock woolly adelgic.

There are also other benefits to microinjection such as safe distribution, ease, and cost effectiveness Most importantly, microinjection allows distribution that produces no spray drift and limits any direct contact with the chemical. New developments in microinjection technology have led to completely self-contained applicators with a lower risk for chemical spill. There is little ?EUR??,,????'??collateral damage?EUR??,,????'?? to other insects or animals, and most importantly, yourself.

This Tree Tech unit at the base of a tree is hermetically sealed and made of two interlocking plastic sections welded to a funnel-shaped dispenser tube. An O-ring and a special locking mechanism maintain pressure to aid solution dispersion into the tree?EUR??,,????'???s vascular system.

Modern Day History

Modern day microinjection techniques began at the turn of the century after Jim Mauget, a chemical supplier, in 1948 was inspired after being on an IV in a hospital. Mauget teamed up with Dale Dods, a chemical engineer, to form the J.J. Mauget company, which released its first microinjection product, Injecticide B, in 1964.

The Mauget technique features a compressible metal ?EUR??,,????'??feeder tube?EUR??,,????'?? with a diameter of 3/1 6” that is driven into the xylem with an insertion tool to the correct depth. The equipment comes with instructions as to how deep it is to be inserted, depending on the diameter and type of the tree.

A capsule containing the desired chemical is attached to this feeder tube to allow the material to enter the tree. It is low pressure, with the intent that the tree will ingest the insecticide into its vascular system at its own rate.

As Mauget continued to improve upon their technology, other developments in microtechnology came from other companies like Tree Tech, ArborSystems, Wedgle Systems, Rainbow Tree Care, and Arborjet. For instance, Tree Tech in Williston, FL patented an injector that is leak proof, pressurized in a way that it doesn?EUR??,,????'???t leak air. An O-ring gasket is one feature included in the unit to prevent leakage. It provides a ?EUR??,,????'??closed?EUR??,,????'?? delivery system which limits the potential to be exposed to the chemical directly.

Tree Tech?EUR??,,????'???s units are available with several kinds of insecticides, fungicides, and fertilizers. Recently, Tree Tech released injectors filled with Merit, a form of imidacloprid manufactured by Bayer.

The Mauget system is the pioneer of modern day of Microinjection. The only tool needed for its installation is an electric drill. The ease and simplicity make it an attractive option for smaller projects.

Other types of injection procedures include ArborSystems and Arborjet. Chip Doolittle of Arborsystems had a concern with standard microinjection units that, during the process, air can be introduced into the tree, which, in turn, can lead to decay. Doolittle realized that trees compartmentalize areas that have been wounded or injured. He sought a way to get the pesticide directly to the tree?EUR??,,????'???s vascular system without drilling and wounding the tree.

Doolittle patented the Wedgle system, which uses a wedge-shaped insertion needle and a high-pressure injection unit. The tip stops at the sapwood of the tree and the chemicals are injected into the tree?EUR??,,????'???s cambial tissue, where they can be dispersed by the vascular system. Since no holes are drilled into the tree, there is minimal wounding, although it can be difficult to avoid chemical leakage.

A fourth approach came from Arborjet, which was founded in 2000 by Peter M. Wild, owner of Boston Tree Preservation. Wild was also seeking to find a way to control the invasive hemlock Woolly Adelgid and sought to minimize tree damage. His prototype involved modifying a needleless medical injection device.

Where Arborjet?EUR??,,????'???s system differs from the Wedgle is that as a micro-infusion device, it does not depend on bark separation, and is designed for low to high volume injections. Instead, the Arborjet system relies on a tiny plug, which is secured into the tree and provides access for the pressurized liquid to enter.

Since microinjection is relatively new, ongoing research among all the companies will continue to determine the full effects of microinjection on the tree?EUR??,,????'???s health, the safety of the process, and the long-term effects.

Many microinjection companies present thorough information and research studies, so for a large project it is a good idea to compare the information directly to decide which system is best for you.