Microinjection is an effective, easy-to-learn technology that facilities and maintenance departments can add to their bag of tricks. Startup cost is not prohibitive. Doing some jobsÑespecially in tree careÑcan require equipment running into the tens of thousands of dollars. Start-up for microinjection is minimalÑin many cases just the cost of the treatment capsulesÑthe small, chemical-bearing canisters that are tapped into a treeÕs trunk. Most of the tools required are already sitting in your tool box.
ÒItÕs very easy to learn,Ó said Robert Ryan of RPW Services Inc. in Fullerton, Calif. ÒYou get the hang of it after a few trees. Then, with a few more applications you learn a few tricks and your speed and efficiency pick up.Ó
In addition to microinjection, RPW also takes care of weed and rodent control for a large number of Southern California cities, homeowners associations and educational facilities. The simplicity of microinjection means that despite the thousands of trees the company treats each year, RPW makes do with a staff of less than 20.
A recent job completed in Irvine, Calif. highlights some of the numbers and dollar amounts involved in a microinjection job. A homeownerÕs association hired RPW to treat close to 400 red gum eucalyptus trees for the lerp psyllid (Glycaspis brimblecombei), an insect that has decimated the trees in Southern California. The cost can vary by distributor, but the following figures give a good idea of what it costs to treat a tree and the amount of profit involved per tree.
The per-case cost of the insecticide capsules depends on the distributor and the number of cases purchased. With their high volume, RPW gets a lower price on the chemical than a small-volume purchaser might. The Imicide (imidacloprid) insecticide used to treat the eucalyptus trees costs up to $27 per individual tree. A crew of six completed the 400-tree Irvine job in two days. The workers used close to 1,400 capsules on the job.
A more precise idea about microinjection chemical price rates can be found on distributor Web sites.
The steps involved in microinjection will vary depending on the manufacturerÑand there are several. The J.J. Mauget Co. pioneered the use of small capsules that are tapped into a trunk. Florida-based Tree Tech offers a similar system, although the formulas in its capsules differ. ArborSystemsÕ method employs a reusable hypodermic needle.
Each company offers training and technical support for its products. All the methods are quick and easy compared to other pesticide application methods, but operators need to remember that handling any potent chemical requires careful label reading and following of directions. Federal EPA regulations call for technicians to wear safety glasses, long sleeves, boots and rubber gloves when working with the chemicals. (Rules vary depending on the chemical usedÑsafety guidelines are provided with each product.) Some of the chemicals are more toxic than othersÑand some pose special risks to amphibians and other aquatic creatures. It always pays to read the labelÑand follow the rules.
