Talking Trees with Lily and Jad . Welcome to our Thursday episode of Talking Trees , where every week we dedicate time to consulting arboriculture . This week we're tackling a critical topic in the field tree risk assessment , with a special focus on methods and approaches which we can use .
We'll explore how trees respond to mechanical stress , adapt to environmental challenges and what signs to look for when assessing the structural integrity of a tree . Let's get started .
Welcome to a deep dive For everyone out there working with trees in public spaces , parks , streets , campuses , you know anywhere . People and trees kind of got to figure out how to get along . And today we're going to tackle this whole thing about keeping trees around but also making sure they're not going to fall on anybody .
Yeah , it's a tough balance to strike right . I mean , we're not talking about statues here . Trees are living things in a constantly changing world here .
Trees are living things in a constantly changing world Exactly . And to help us unpack all of this , you've brought us research articles , strategy documents , even a guide for a tree risk assessment app . It's a lot .
Well , it's a complex topic . I think the variety of materials really shows just how much goes into making sure trees are a benefit to public spaces and not a danger .
So , when you're looking at all of this as someone who works in this field , what's the first thing that grabs your attention ?
It always comes back to that central challenge of finding a balance . We absolutely have to minimize the risk of trees failing , but we also don't want to lose sight of all the incredible things trees bring to the table . Yet a world without trees would be yeah , let's not even go there . Yeah , so it's not about eliminating risk completely .
In fact , one source called it a common sense . They get diseases , they're part of a whole ecosystem . It's really about managing the risk we can control , not pretending we can get rid of it entirely .
So instead of asking is this tree safe , we should really be asking what .
We should be asking okay , what's the level of risk here and what can we do about it ?
Hmm , that's really what tree risk assessment boils down to . It's about looking at the likelihood of a tree failing , what could happen if it did fail , and even things like how many people are actually in the area , because risk isn't just about the tree itself , right , it's about what's around it and what could be impacted .
That makes sense , and I'm seeing some of these sources talk about different systems for actually measuring this risk . We've got TRAQ , qtra , valid . Can you give us a quick overview of what each of these brings to the table ?
Sure , let's start with TRAQ . That stands for Tree Risk Assessment Qualification and it's from the International Society of Arboriculture . Now , TRAQ itself isn't really a calculation . It's more about making sure the person assessing the risk actually knows what they're doing .
So someone with TRAQ certification has gone through the ISA's training on best practices , which is really important as a foundation .
So it's making sure the assessor is competent Seems like a good place to start .
Absolutely . Then you've got QTRA , which is Quantified Tree Risk Assessment . This one's all about putting numbers to the risk , so using probabilities and statistics to figure out the actual likelihood of a tree causing harm .
I can see how that would be useful , especially if you have to explain decisions about a tree to people .
Absolutely . One source I was reading actually mentioned how the chance of someone getting killed by a falling tree is way lower than the chance of dying in a car crash , and QTRA is really helpful for putting those risks into a more relatable context .
That's a great way to put it into perspective . Ok , so we've got TROQ for the assessor's expertise , we've got QTRA for quantifying the risk . Where does valid come in ?
Valid is really big on being practical . It focuses on things that pretty much anyone , even without tons of training , can pick up on like obvious signs a tree might be in trouble . So think like huge cracks in the soil around the base of the tree branches that are hanging down at weird angles , if the whole tree is suddenly leaning more than it used to .
These are all red flags that even someone who doesn't work with trees can often spot .
So it's a way to prioritize , like if you see those obvious signs , then you know it's time to dig a little deeper .
Exactly and Valid has this really smart tiered approach . There's the basic level , which is often enough , but if needed it can be bumped up to a detailed assessment or even an advanced assessment , depending on what the situation calls for .
It sounds like each method has its own strengths , so how does someone working in the field decide which one is best for a given situation ? Because I'm imagining a quiet corner of a park versus a street lined with trees near a school might lead to very different approaches .
You're absolutely right . Context is key , the level of detail you need , the resources you have available , time , budget , how much expertise you've got on hand it all factors in . And yeah , a quiet little corner of the park versus a busy street lined with trees next to a school . Those need totally different approaches to risk assessment .
So , even with these established systems , there's still room for flexibility . It's not just okay . Here's the formula . Apply it to every tree , which I imagine is a relief for the people out there dealing with a thousand different tree situations every single day .
It has to be . Remember we're talking about living organisms here , and just like no two trees are ever exactly alike , no two risk assessments are going to be identical either .
Speaking of things that aren't always identical , something that really struck me in these sources was how much emphasis they put on public perception . Even if , statistically , a tree is low risk , if the public is concerned about it , that matters . Why is that such an important part of the equation ?
Because , when it comes down to it , managing public spaces also means managing how people experience those spaces . Right Fear , even if it doesn't perfectly line up with the actual risk , is still a factor . I've seen cases where a tree was statistically pretty low risk but there was so much public concern , so much worry , that it ended up being removed anyway .
So you've got this balance to find between what we understand scientifically and how people are actually feeling and reacting .
So how do you bridge that gap ? Because it doesn't sound like it's as easy as just saying well , the numbers check out so you don't have to worry .
No , it definitely isn't . This is where being a good arborist means more than just knowing your trees . It means being a communicator . It's about explaining your assessment in a way that makes sense to people who aren't tree experts , so they can understand it and trust your judgment .
And sometimes it's about getting creative , finding solutions that address the actual risk but also take into account how people perceive that risk .
So it's not just about the science , it's also about that human element . This is fascinating and , honestly , all this talk about assessment makes me want to know more about how you actually do it . Like , what are some of the things you look for when you're evaluating a tree in the field ?
It starts broad . It's kind of like when you go to the doctor they ask about your overall health and lifestyle . Same with trees . We look at the tree's environment . What are the growing conditions , like Soil type , how much water is available ? How much wind does this tree have to deal with ? Even the history of the site can be important .
All of those things contribute to a tree's health and how stable it is .
So you're basically doing environmental detective work before you even look at the tree itself .
Exactly . You need that context . Then you can move on to the tree itself . How old is it ? How fast does it grow ? Are there any weaknesses that are common to this species , especially as it gets older ? We look at the whole structure of the tree the branches , the canopy , the trunk . All of those visual clues tell a story .
And some of those stories are easier to read than others , I imagine . Are there any like telltale signs that immediately make your antenna go up as an arborist ?
Oh , definitely If you see big cracks in the bark or in the trunk itself . Mushrooms growing around the base of the tree can be a bad sign . Dead branches are obviously something to pay attention to .
If the tree is leaning significantly or if you notice wounds or cavities that are exposing the wood inside , those are all red flags and , depending on how severe they are , they might mean it's time to do a more in-depth assessment .
Okay , so you spotted something that needs a closer look . What happens then ? What does a more advanced assessment look like ?
Well , that's when we bring in the more sophisticated tools , things like sonic tomography . Sonic tomography yeah , it's kind of like giving the tree an ultrasound , actually , oh interesting . So we use sound waves to create a map of what's going on inside the tree .
That way we can see things like decay or cavities that we wouldn't be able to spot just by looking from the outside .
That's amazing . You can see inside the tree without having to cut it down .
It really has changed how we assess risk , and it just goes to show how much tree care is always evolving . You know , we're constantly learning new things about trees , developing new technologies that help us understand them even better .
Which brings us back to those systems we were talking about before TOAQ , QTRA , valid . Do you think any of these is going to become like the gold standard for tree risk assessment in the future , or is it always going to be about choosing the right approach for the situation ?
I think it's always going to be about finding the right tool for the job honestly , because every tree is different , every situation has its own quirks and these methods they all have their own strengths and weaknesses .
So the important thing is to understand those nuances and then you can choose the approach that makes the most sense for that particular tree in that specific environment .
So it's not about trying to force every tree into the same box . It's about learning how to listen to what each individual tree is telling you and then using that knowledge to make the best decisions .
Exactly that's what I love about this field . It's this blend of science and art and a deep respect for the natural world .
This has been an amazing deep dive . So for our listeners out there , the people who are dealing with these exact challenges every day , what's the one thing you want them to take away from this conversation ?
I'd say remember this every tree has its own story and it's written in its rings , in its branches , even in the way it stands . The better we get at reading those stories , the better we'll be at keeping our trees healthy and making sure that everyone stays safe .
Well said . And for anyone who wants to explore this topic even further , be sure to check out our show notes . We'll have links to all the resources we talked about today . Thanks for joining us on the Deep Talk .
That wraps up our Thursday episode of Talking Trees , where we focused on tree risk assessment and the methods used to evaluate a tree's structural integrity . Thank you for tuning in to our Arboriculture Consulting Series . Be sure to join us tomorrow for more expert insights and practical advice .
Until then , take care of your trees and keep exploring the wonders of arboriculture . Thank you .