|CHEMJET® - Why Trunk Injection
Photos and illustrations -
Copyright Chemjet Trading Pty,Ltd, Australia
Plant protective fungicides, insecticides and nutrients applications has become an indispensable component of quality assurance in arboriculture, in which the control of insect pest, fungal and canker infections. CHEMJET® , micro-injection targets the problem directly within the tree itself. Control sanctions on chemicals, application methods of plant protection will become more severe in years to come. It is this new awareness for the environment, that will demand and dictate, the use of better chemicals and application methods in the treatment for trees.
Texas A & M protocol for flare root injection is to remove 3-4 inches of soil around the root flares in-order to perform the injection, upon completion replace the soil and debris back around the root flares. This introduces pathogenic infections into the dill sites which all too often resulting in canker infections that delays wound closure. Supposedly, the injection in the root flares, provided bi-directional movement, root pressure was also a consideration to assist faster uptake and faster wound closure. All these conclusions are wrong; root pressure has no effect on uptake, photosynthesis pulls the water up to produce food in the leaves. Movement downward occurs only when the water column in the tree is broken by air that is allowed into the tree during drilling. Movement downward is not extensive and should not be counted on to provide significant control below the injection site.
Furthermore, when the injection sites are covered over with dirt and debris, we are not aware of the extent of all the damage inflicted both the internal and external. We do not visualize, the insect invasion, bark separation, wound closure failure, weeping caused by wet-wood, canker growth or soil borne pathogens. Injuries in the root flare below soil level tend to be slow to recover because of all the above factors, and the greatest drawback is the tree’s lack of ability to stimulate only limited wound closure.
The root or trunk flare is the critical transition area from the roots to the trunk, supplying water and nutrients to the canopy for food production. This critical zone is the life line of the tree. Excessive and repetitive damage can and will cause eventual death. This has been well documented in Tree and Turf articles regarding the damage caused by lawn, landscape equipment and weed eaters, which is one of the leading causes for tree death. Repetitive injection with the numerous 5/16"drill portals causes similar results as previous mentioned regarding insect and disease invasion.
The injection application on a 12 inch diameter tree around the root flares, would require upto approximately 20 drill portals of 5/16” diameter. With trunk stem injection, it would require only 12 injector syringes spaced 3" apart around the trunk stem, the drill size is 11/64". Which is half the size and almost half the number of drill portals.
I was fortunate to discuss this dilemma with two Plant Pathologist from Australia, one in Italy, and one in Germany and none had too many favorable comments about below soil injection. They explain the logic and reality of trunk stem injection, in simple terms of getting the job out of the dirt, away from soil borne pathogens, insect invasion, canker infections, reducing the drill size and number of drill portals and much faster wound closure. Equally important was the uptake from trunk stem injection, it achieved greater efficiency and distribution throughout the tree's canopy, as it is beginning of the constricted bottleneck of the upper trunk stem. In Oak trees the water movement is at the rate of 92 feet per hour and therefore, providing a thorough and a very rapid chemical distribution, with minimum overall damage to the tree. The one most important factor is that wound closure is much faster and more efficient up the trunk stem extending from above the trunk base to upper branches as it is associated with stem growth and the annual increase stem diameter. Meristem cells (similar to stem cells in humans) display an important role in regeneration and wound closure ... and the tissue layer known as cambium.....
The Chemjet Injector Syringe, (Australian made) one of the best micro injection systems that is now available on the market. Chemjet® has more that twenty five years of field application and is used worldwide. The injector can be filled to 5,10, 15,and 20 mils providing a more accurate prescription application. It is a re-usable, spring loaded syringe which is very practical, and unlike the pre-filled injection capsules, are one time use disposable products. The Chemjet® can be re-used 1000 times with proper care and handling.
The Chemjets, delivers the same prescribed volume of the fungicide ( Propiconazole 14.3 % MEC ) at the preventive rate of 10 mils per diameter inch, in a 50% concentrated solution measured at 20 mils per injector and placed 3" apart around the tree above the trunk flare. Unlike the macro injection system, with a very high volume water at the rate of 10 mils of fungicide diluted per liter of water. Often times, the tree will not absorb the full prescribed amount of fungicide / water solution, leaving as much as a 1/3 or more of the product in the tank. The Chemjet procedure with the higher concentration is much like a booster shot of an antibiotic, only with far more effective results, as the application uses the water within the tree for dilution and transport to the leaves and distribution throughout the entire tree. The damage factor with the Chemjets, are far less invasive and the wound closure, due to the small shallow holes 11/64" will close within a few short weeks. The macro drill size 5/16"takes a longer time for closure partly due to the dirt at the drill sites. Excessive damage to the trunk flares, limits the water and nutrient movement to and from the roots and can rob the tree from vigor, good health or cause eventual death.
The most rapid movement of water is up through the trunk stem from the roots to the canopy. Concluding, the trunk stem is the most effective location for injection sites, maximizing uptake and distribution, and at the same time minimizing wound effects, pathogenic infection and all the while protecting the ENVIRONMENT.
After more than a year, I am satisfied with the performance of the Chemjet Tree Injectors. They provide very efficient delivery, minimal wounding, protective of the environment and very labor saving. The chemjet® is reusable, and is used worldwide for more than 25 years on annual injections and the trees continue to prosper showing vigor and good health.
IMPORTANT NEWS - More than 40 years of suppressed research !
Trunk Stem Injection / Infusion
Trunk stem injection / infusion was the first injection method used, probably because it was convenient for the applicator. It was found to be problematic in Dutch Elm Disease because injection ports were deep, ( penetrating several growth layers or sap wood ), uptake was not guaranteed and the ideal sink was often missed. Injection ports were later developed and applied a shallow-pit trunk injection technique in which fungicides were pressure injected into very shallow drill injection ports of the three outer most growth rings. This technique found high comparability in the translocation uptake relative to root flare injection method as water movement is very rapid up the trunk stem which, moves at the rate of 92 feet per hour.
Although wound closure of the shallow portals that are drilled in the trunk stem 4.5 ft above the soil level was relatively quick within 6-8 weeks. However, clients often objected to the visible, large, open injection ports which were 1/2 in diameter placed 3-5 inches around the trunk stem. Thus, it was concluded that the next best injection site would be the root flares 4-5 inches below soil level which, indeed, has become the chosen technique and standard site for tree injection. This was ideal, as it quelled the client from any further objection since the damage was no longer visible and also the extent of damage was totally out of sight as well. It was not important to research the uptake, the damage factor nor the effects of microorganisms, pathogenic infections and eventual decay at the injection sites, as it's only purpose was to appease the objections from the customer.
The drill port ! Is actually 1 inch scale - I----------I
I---------------I The 1" shallow pit port. Later comes the 1/2" O portal and years later, it was reduced to the 5/16" dia. Now, imagine these gapping holes all around the trunk stem. It was sure best to hide something like that, all for the benefit of science!
There you have it, the real facts were stalemated to cover up the lack of research, a sort of cook the books situation. Would it not have been better to just have the injector tees made smaller to reduce the unsightly damage in order to maintain the integrity of the trunk stem micro-injection research ? The real research was suppressed for 40 plus years with, a don't tell, don't explain and see no evil policy so that, the root flare MACRO-INJECTION would appear to be the result of indepth research. No further explanation was necessary. Political agenda and VERY - VERY Shanky Science?