Rainbow Treecare Position Summary:

What Our Experience Tells Us about Arbotect and Alamo in Protecting Trees from Dutch Elm Disease

• Rainbow Treecare treats approximately 8000 elms on a 3-year protection cycle.  We use Arbotect in the protection of those trees.  Our loss rates average about 1%.  Every treated elm is surveyed at least once, every three years, by one of our certified Arborists.  That’s an extra service many companies don’t offer.
• Rainbow protects more trees from Dutch Elm disease than any company in the United States.
• The vast majority of companies treating elms in the U.S., who switched from using Arbotect to Alamo (propiconazole) in the late 1990’s (with promises of results similar to Arbotect -- and faster on-site treatment times and lower costs) returned to Arbotect after substantial elm losses during the second and third years of the protection period.
• Rainbow Treecare treated 500 elms with Alamo (propiconazole) in the late 1990s in the Twin Cities and found that the treatments worked, but only for one year.  Following those initial years we experienced major losses.  This was very costly to our clients and to our company.  Please see Wachtel (in the Milwaukee area) and Swingle Lawn, Tree, & Landscape Care (in Denver), which experienced similar results (Wachtel experience & Swingle experience).  Their results and conclusions are posted on our web site.
• Annual treatments are a possibility with Alamo (propiconazole) – but the issue of annual wounding (at the root flares for the injection process) and early season infection (pre-treatment) are reasons for concern.  Given the wounding issue, and the fact that Alamo (propiconazole) does not move into annual new wood (necessary to give the tree the protection it requires), makes it clear to us that Alamo (propiconazole) fungicide does not offer a viable long term protection option.
• We have observed some therapeutic value with Alamo (propiconazole) during the first growing season following treatment.  However, we have never actually experienced saving an infected tree using Alamo (propiconazole) (arresting the disease).  Eventually, each time, the fungus has overcome and claimed the infected tree.
• By using Arbotect on a three season application cycle, via the macro-infusion method, we have protected literally thousands of elm trees from Dutch Elm disease across the Twin Cities area.  The same has been true for other tree care companies across the United States who have adopted this same strategy.
• Virginia Polytechnic Institute and State University did a major study on Alamo (propiconazole) and its persistence.  They could not find evidence of the chemical, at high dosage rates, in studies of treated trees eight months following injection.  It was determined that Alamo (propiconazole) DID NOT move into the tree’s new growth wood.
• Two other research papers have also been published by the University of Minnesota and North Dakota State University, both recommending the use of Arbotect as the best chemical protection strategy against Dutch Elm disease.
• Two other published studies, by Mark Stennes (Dutch Elm Chemotherapy with Arbotect 20-S and Alamo) and R. Jay Stipes (The Management of Dutch Elm Disease) both support observations that Arbotect fungicide does in fact move into new wood (and offers multi-year protection), whereas no such observations have been documented for Alamo (propiconazole).
• We provide a three season treatment guarantee with Arbotect (treatment money back during the coverage period if infection occurs), but only a one season guarantee with Alamo (propiconazole) (ask for a copy of these detailed guarantees from your Rainbow Arborist).  Our first fungicidal recommendation, for uninfected trees, is always Arbotect.
• Some generic, Alamo-type chemistries have recently made their way into the U.S. market.  We have nothing to do with these chemistries.  We do not know that these products truly represent the chemistry found in propiconazole.   These products are untried, untested, and uncontrolled.  Therefore, we cannot support the use of these products in any way.  Consumers approached to purchase these untested chemistries should be extremely wary.
• Rainbow Treecare offers mastery in the other (non-chemical) elements of DED management as well, including: neighborhood sanitation protocols, experienced tree climbers for whole tree inspections, isolation and tracing techniques, implications of root grafting, trenching and girdling expertise.
• Rainbow currently employs 30 ISA certified Arborists, with approximately 200 years of collective tree care experience that comes to bear when protecting valuable Twin Cities trees.  Nearly all of Rainbow’s arborists hold college degrees in forestry, urban forestry, or horticulture.  Rainbow has the experience and the formal education to make recommendations that are based on a weight of hard facts, and not isolated conjecture.
• Rainbow Treecare’s sister company, Scientific Advancements, is the sole distributor for both Arbotect and Alamo (propiconazole) fungicides (manufactured by Syngenta – formerly Novartis) to other tree care companies throughout the United States.  We truly understand these chemistries and how they best fit within the context of a comprehensive battle against Dutch Elm disease.  Our first recommendation, given the university studies and our years of our personal experience, is to select Arbotect as the # 1 choice in elm protection chemistries, as part of a comprehensive elm protection strategy.  Alamo (propiconazole) is ideal for controlling Oak Wilt fungus, but not Dutch Elm disease.

Release Date:  06-05-06

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