The core principle of ethics in medicine relating to the treatment and medication of a patient is to “do no harm,” part of the Hippocratic Oath. This doctrine is applicable whether treating humans or trees.
What is the best way to treat trees? Just Google “tree care” to see endless pages of products, with businesses offering their services and solutions. And you’ll notice there’s a variety of solutions competing to treat the same tree disorder. Which one is better? Is one the best? Possibly, but which one often depends on who you ask.
If you stopped a passing Sumerian some 4,500 years ago for any arboricultural hints for pest or disease management, the prevailing logic of the day may have shaped his or her response. “In Mesopotamia, we’re not finding any downside to sulfur dusting our trees.” Why?
The evolution of modern tree care paralleled the understanding of bacteria and diseases beginning in the 17th century. A greater understanding of diseases and their origins has led to advancements in tree care.
Treating trees might seem confusing when factoring in that, for every host tree, there could be hundreds of threats from abiotic (drought, floods and forest fires) and biotic inducers. Biotic disorders are differentiated by their cause (bacteria, fungi, viruses, phytoplasmas, nematodes, insects, mites, etc.). In most tree scenarios, pathogens are parasites. However, not every pathogen is a parasite, and each parasite is not a pathogen. It can be a bit baffling if you don’t know what you’re doing.
Tree-disorder identification considers signs and symptoms. Signs are some manifestation of the insect or pathogen itself (e.g., white pine blister rust). Symptoms are how infections affect a tree (e.g., defoliation, crown thinning, decay, wilt, etc.). (Photo 1)
There are many approaches to treating a tree, and within those platforms are various delivery systems and application techniques, all with the goal of restoring the tree back to a healthy status. The contention of this article is that micro-
injection of trees is a vastly superior application method compared to other delivery methods of tree treatments when considering the patient, the applicator and the planet. Micro-injection technology also adheres to our credo of doing no harm in the forest, rural or urban.
After World War II, spray treatments were the established practiced for plant care. This lasted until the early 1970s, when the harmful effects of DDT brought negative attention to spraying. The challenges inherent to spraying are numerous, but unwanted drift is the main complaint. Beyond the over-spray of the juice from the nozzle hitting past its intended boundaries, depending on the wind and other conditions, spraying carries pesticides and the like to other adjacent plants and animal life, often causing collateral damage and even the demise of the unintended target. Spraying also can be harmful to the applicator if proper safety protocols aren’t followed.
That said, spraying is the benchmark that all other treatments are measured by to this day. The plus side of spraying is it is faster when measuring in acreage. “Time is money” often outweighs the possible harm caused by spraying.
Micro-injection in its inception was perceived as an alternative to spraying. In the last half-century, tree-injection technology, including root and bark treatments and their devices and delivery techniques, have advanced profoundly. Injection is currently the most popular method for control of damaging insects, pathogens and nematodes in landscape tree care.
Tree injection – also known as trunk injection or stem injection – is a delivery method that targets a disease or pest with a precise measurement of insecticides, fungicides, antibiotics, plant nutrients or fertilizers. Injecting into the xylem of a tree utilizes the tree’s vascular system to translocate, or distribute, the active compounds into the wood, canopy and roots, where protection or nutrition is needed. (Photo 2)
Trunk injection of pesticides delivers a precise amount of compound, reducing the negative impact of pesticide drift into the environment that occurs with aerial or ground spraying. Spraying also requires the application of a higher rate of chemical than a trunk injection to compensate for the drift that does not reach the intended target.
Earlier, I mentioned that spraying is faster than tree injections when calculated by acreage. Rather than focusing on speed, the better question to ask is, what is the efficacy of mass spraying?
When mainlining into the tree’s vascular system, the effects of tree micro-injections often can be witnessed in minutes. In a short amount of time, the tree or shrub will begin taking up the material from the injection and distributing the chemicals throughout the entire tree, from roots to crown. I contend that using micro-injections for tree health care delivers faster and more effective results than traditional spray methods, costs less in dollars and leaves a smaller footprint in the forest.
One objection sometimes raised with tree injection is the potential negative impacts of drilling the tree. There’s no denying that a three-quarter-inch bore into the tree is one of the steps involved with micro-injection. An eleven-sixty-fourths, hi-helix drill bit is recommended to minimize damage to the tree. But a study conducted by Dr. T. Tattar, professor of microbiology at the University of Massachusetts, compared the treatment of trees with micro-injections to the pruning (including topping and crowning) of a tree. Dr. Tattar’s research showed, “It would take 35 injection sites on a tree to exceed the area of a single 1-inch branch cut on the trunk.” (Photo 3)
Once the tree is drilled, the tree begins the recovery process known as compartmentalization of the wound. If done correctly by professional applicators, drilling isn’t what kills a tree. Disease, pests, environmental interference (natural or man-made), neglect and other challenges are what lead to a tree’s demise.
Just as with any medicinal treatment, there has to be a balance. What is the desired objective or intended result you’re striving to achieve? Hopefully, the objective result is the recovery of the patient to a quality of life that justifies the labor, expense and required treatments inherent to the process.
Following the science of micro-injections is your best advantage in achieving that balance. Using these tips will help ensure your success.
- Administer only researched and proven chemical formulations appropriate for the treatment plan.
- Take informed precautions, such as disinfecting drill bits between trees.
- Do not shortchange the patient with weak formulas or by “cutting butter with a chain saw” (overtreating) to save time.
Micro-injection is based on incorporating protocols and standards built upon experience from decades of treating trees, always with an eye to the future for developing new technologies and techniques. And it’s good for the forest.
Kellie Butterfield Dodds is president & CEO of Mauget Company, a 20-year TCIA corporate member company based in Acadia, California. She was assisted by Mauget staff with writing this article.
