Best Management Practices

We sat down with authors of the newly released Tree Injection Best Management Practices to discuss its importance

Dr. E. Thomas Smiley, Plant Pathologist and Soil Scientist with the Bartlett Tree Research Laboratories along with Shawn

Bernick, MS, the former Director of Research and current Chief Operating Officer for Rainbow Treecare Scientific Advancements are the co-authors of the International Society of Arboriculture’s (ISA) Tree Injection BMP.


Shawn Bernick MS: The intentions of the BMP were to create some consistency and common ground where we could. Regardless of the device or tree injection equipment that you were using as an applicator, there are some recommendations that will minimize any adverse affects of tree injection but will also help in the performance of the different products that are being applied. That was one impetus for it, and there were companies out there making recommendations about how it should be done and there was not consensus among industry and scientists on that, so there was confusion among technicians.

Dr. Tom Smiley: We pretty much focus on generalities of where, when, and how to apply because those are some of the common issues we see in the industry. One of the major issues we see is people trying to inject into tree trunks when we should be injecting into root flares. We get a lot of questions about what time of day materials go up more quickly, so we tried to answer those common questions and point people in the right direction for doing tree injection.

I think the devil is in the details on these things, so getting the industry on the same page is a huge contribution.

Dr. TOM SMILEY is a scientist with the Bartlett Tree Research Lab and a frequent speaker at arboricultural events.
Photo: J. Kolarik/NE ISA


TS: There is certainly a lot of product-based research out there showing that this material works on this pest. There’s a number of studies that date back to the Dutch elm disease years – the 70’s and 80’s – that cover some of these more general topics and because of the age of that research a lot of folks just don’t know about it, so we tried to put it together in a more readable form so they could find it more rapidly.

SB: That was one of the challenges with putting the BMP together – taking information from the industry that there may or may not have been replicated research on and then coming to a consensus on those industry recommendations. We just didn’t have published research to fall back on so we had to rely on industry experience for many of these recommendations.
TS: That’s the same for many BMPs. They are based on what is done in the field, not necessarily what is known in the research. I think smart and opportunistic researchers can look at these BMPs and probably find at least a dozen opportunities for further research studies. Certainly, we do that here at the Bartlett Lab. Sometimes it’s a quick experiment and sometimes it’s a longer experiment but it can guide future research to answer some of these questions.

SHAWN BERNICK, MS has been involved in the development of tree injection research with the USDA-FS and Rainbow Ecoscience for 15 years


SB: A big distinction to get the industry aligned on, Tom alluded to it earlier, but the importance of doing injections into the root flares versus higher up on the trunk – that’s an important one. Traveling the country and seeing a wide range in the way that companies do their applications, everywhere from up at eye-level to down on the root flare to spiraling around the tree – all over. So getting root flare placement established was key.

Then, the importance of drilling is oftentimes overlooked, I think. Having sharp drill bits – cutting clean holes – like a surgeon would do, and putting focus on those techniques. I think the devil is in the details on these things, so getting the industry on the same page is a huge contribution.

TS: That’s right.

SB: One distinction right away we wanted to get across is that tree injection is just one methodology one might use to manage insects, disease, or tree health issues and what factors might lead you down the decision tree to using tree injection and that it has it’s pros and cons from a ‘tool in the toolbox’ approach – that was #1.
Then, #2, as you make the decision to use tree injection, ensuring that you are following some of the guidance on the practices around root flares, drilling, injection site placement – some of the key distinctions that are in there regardless of the device you are using. Then #3 – I see an opportunity with the specifications, especially with the invasive species, emerald ash borer treatments that are going on with municipalities and government entities, to create a consistent approach to bidding the work and performing the work.

Read the full interview