#tree care

We have an old sugar maple in the backyard that has two main trunks coming up from almost the same spot near the base. I never thought much about it. It looked like a tree, it had been there longer than we had owned the house, and every fall it did the thing sugar maples do where the whole yard turns orange for about two weeks. Then last spring, after a rough windstorm, I walked outside and saw a crack running down between the two trunks that had not been there before.

I did what most people probably do, which is spend way too long looking at photos online trying to diagnose a tree myself. What I found out eventually, from someone who actually does this professionally, is that the crack had almost certainly been building for years. The two trunks met at what is apparently called a codominant union, and because they grew so close together, bark had gotten trapped in the joint instead of the wood fusing solidly. That is a known weak point, and ours had finally reached its limit during a strong enough wind event.

What really got me was finding out sugar maples are apparently one of the more common species for this exact issue. Something about how they tend to branch low and close together when they are young, and if nobody ever corrects that structure with early pruning, you end up with two roughly equal trunks competing for the same space decades later. Ours was probably planted sometime in the seventies based on its size, so whatever early pruning might have prevented this was never going to happen at this point.

What I Learned About the Fix

I assumed the tree was probably done for. What actually happened was a cable installation, not a repair exactly, more like a management system. The idea, as it was explained to me, is that a flexible steel cable gets installed higher up in the canopy to limit how far the two trunks can move relative to each other in wind. It does not glue the crack shut. It reduces the leverage that caused the crack to form in the first place, which lowers the chance of the whole thing failing outright in a future storm.

There is apparently a whole standard for how this is supposed to be done, something called ANSI A300, which covers where the cable gets placed, what hardware gets used, and how often it needs to be checked afterward. I had no idea tree support installation was this regulated until I went looking into it. It is not just wrapping a cable around a tree and calling it done.

The install itself was less dramatic than I expected. A guy went up into the canopy on a rope, set two eye bolts into solid wood on each trunk at what he said was about two thirds of the way up from the split, and ran cable between them. The whole thing took maybe two hours. He also mentioned it would need to be checked again in a couple of years, since as the tree keeps growing the hardware needs to be re-tensioned or repositioned so it doesn't start cutting into the bark. That part surprised me. I assumed once it was installed, it was just done.

What the Assessment Actually Looked Like

Before any of the cable work happened, there was an actual assessment first, which took longer than I expected for what I thought would be a quick look. He walked the whole tree, checked the union from a few different angles, tapped on the trunk in a couple of spots listening for anything hollow, and asked how long we'd owned the house and whether we'd noticed the crack getting worse recently. He also asked about drainage in that part of the yard, since apparently saturated soil after storms can be part of what pushes a borderline union over the edge. I hadn't thought about our yard's drainage having anything to do with a crack forty feet up in a tree, but apparently it can matter more than you'd think.

What I Would Tell Anyone With a Similar Tree

If you have a tree with two big trunks meeting at roughly the same point, especially an older one, it is worth getting someone qualified to look at that union even if there is no visible crack yet. Ours had probably been weak for a long time before the crack showed up. Catching it earlier might have meant a less involved fix.

I have started looking at other big trees in the neighborhood differently since this happened. There is a maple two houses down with what looks like the exact same low, split-trunk structure ours had, and I keep half wanting to say something to the owners about it. I haven't yet, mostly because I don't want to be the neighbor who shows up uninvited with tree opinions, but if I ever get the chance to bring it up naturally, I probably will.

I also learned that this is not a guessing game you should do yourself. Whether a tree needs a cable, a brace rod, or is honestly too far gone for either, depends on the specific defect, the species, and where the tree is relative to your house. Guessing wrong either wastes money on hardware that does not fix the actual problem, or worse, gives you false confidence in a tree that genuinely needed to come down. I would rather pay for an honest assessment that tells me a tree is fine, or tells me it isn't, than assume either way based on how it looks from the kitchen window.

Between the two tree companies I know of working in this area, Hufnagel Tree and Middletown Tree Service both do structural assessments and cabling work, and either is worth calling if you have a tree that makes you nervous. For background reading before you call anyone, Rutgers Cooperative Extension has decent New Jersey-specific material on tree structure and what different defects actually mean, and I found the International Society of Arboriculture site useful for understanding what a certified arborist credential actually means before I called anyone.

If you're on the fence about whether a lean or a split union is worth paying attention to, I'd say err on the side of getting it looked at. It cost us far less than I expected, and the alternative if we'd ignored it and that union had failed during a bigger storm, potentially onto the fence or worse, would have cost a lot more than a cable and an afternoon of someone's time.

Our maple is still standing, cable and all, and it still turned the whole yard orange last fall. I just look at it a little differently now. I catch myself glancing up at that union more than I probably need to, just checking, and I think that's a fair trade for the peace of mind of knowing someone qualified actually looked at it before we decided it was worth keeping.

There is a version of this problem showing up in a lot of Monmouth County yards right now, usually after a windy stretch, where a tree develops a lean or a crack and the homeowner has to decide what to do about it. I have talked to a few neighbors going through exactly this, and the split in approach is pretty consistent. Some people go the hardware store route and try to brace or stake the tree themselves. Others call a professional right away. Having watched both play out, I think the tradeoff is worth laying out honestly.

One neighbor in particular spent a weekend rigging up guy wires from an old maple to a couple of ground anchors after noticing a new lean following a storm, using stuff he had picked up at a big box store. Another neighbor, with what looked like a similar situation, called someone out for an actual assessment instead. The two outcomes were different enough that it seemed worth writing up.

The Case for DIY

I get the appeal. A leaning young tree, one that was recently planted and just needs some support while its root system establishes, is genuinely a reasonable DIY job. Staking a new tree with proper strapping, not wire that can cut into the bark, is well within a homeowner's ability, and there is plenty of solid guidance out there for how to do it correctly.

The problem is that a lot of the leaning and splitting trees I am talking about are not young transplants. They are mature trees, sometimes decades old, with actual structural defects, not just a root system still finding its footing. That is a fundamentally different situation, and the DIY approach that works fine for a young tree does not translate.

The neighbor who went the guy-wire route was, I think, working off of the same instinct that makes staking a young tree seem reasonable. If wire and anchors work for a sapling, why not for a bigger tree with a bigger problem? The issue is the scale and the type of load involved. A sapling's root system is establishing and needs temporary support against wind while it grows in. A mature tree with a genuine lean has usually already lost some meaningful portion of its root anchorage, which is a different and often more serious mechanical problem that ground anchors and guy wire were never designed to solve.

Where DIY Falls Apart on Mature Trees

A mature tree with a split trunk or a codominant union needs an actual engineering-style assessment, not a strap and a stake. The hardware used for real cabling and bracing is rated for specific loads and installed following a standard, ANSI A300, that covers exactly where it goes and how it is tensioned. Get any of that wrong and you can end up with hardware that girdles the tree as it grows, or a cable placed at the wrong height that does not actually reduce the leverage on the weak union it was meant to protect.

There is also the question of whether the tree is even a good candidate for support in the first place. Some leaning or split trees have defects severe enough, or decay advanced enough, that no amount of cable or bracing changes the underlying risk. Telling the difference between "this tree needs a cable" and "this tree needs to come down" is not something you can reliably figure out by eye, and getting it wrong in either direction has real consequences.

I asked the neighbor who called a professional what the visit actually involved, since I was curious how different it was from just eyeballing the lean. The arborist checked the soil around the base for heaving or cracking, looked at the trunk from multiple angles for any sign of a crack forming, and asked a handful of questions about when the lean was first noticed and whether it had changed recently. That combination of observation and history is apparently how you tell a stable, long-standing lean from an active, worsening one, and it is not something that translates well to a quick look from the sidewalk.

The Guy-Wire Situation, One Year Later

For what it's worth, the neighbor who went the DIY guy-wire route ended up calling a professional anyway about eight months later, after the lean had visibly worsened despite the wires. What he found out was that the anchors had been placed too close to the trunk to provide meaningful counter-leverage, and the wire itself had already started biting into the bark at the attachment point. The fix ended up being more involved at that point than if he had gotten an assessment from the start, since there was now a girdling wound to address on top of the original lean. I'm not saying every DIY attempt goes this way, but it's the kind of outcome that makes the case for starting with a proper assessment rather than a guess.

The part that stuck with me was how confident he had been going in. He had watched a few videos, bought decent quality wire and turnbuckles, and did a genuinely careful job by the standard of what he was trying to do. The problem was never the quality of the work. It was that the underlying plan, treating a mature tree's root plate movement the same way you'd treat a young sapling needing temporary support, was wrong from the start, and no amount of careful execution fixes a plan built on the wrong premise.

What This Actually Costs, for Comparison

Out of curiosity I asked both neighbors roughly what they spent. The DIY materials ran under a hundred dollars, plus a weekend of labor. The eventual professional assessment and cabling work, once he called someone, cost several times that, partly because of the extra complication from the girdling wound that had developed in the meantime. The neighbor who called a professional from the start paid a comparable amount to what the other ended up paying total, just without the eight-month delay or the additional damage. The lesson wasn't that DIY is always more expensive in the end. It was that guessing wrong on a mature tree tends to cost the difference twice.

What I Would Actually Recommend

For a young tree that just needs temporary support while it establishes, DIY is fine, plenty of extension resources cover it well. For anything mature with a visible split, a crack, or a sudden lean, get someone trained in tree risk assessment to look at it before doing anything. Rutgers Cooperative Extension has decent background material if you want to understand the vocabulary first, and the International Society of Arboriculture has a directory for finding certified arborists in the area.

Locally, both the tree service team at Hufnagel Tree and Middletown Tree Service do this kind of structural assessment and can tell you honestly whether a specific tree is a cabling candidate or something more serious. Worth the call before you buy hardware at the store and guess.

Photo by Andreas Maier on Pexels

There's a pattern I've noticed on my street the last few winters, and I don't think we're unusual. The moment a winter storm watch shows up in the forecast, half the neighborhood suddenly remembers they have big old trees. People are out there the day before a storm, looking up at branches, wondering if that one dead-looking limb over the driveway is going to be a problem tonight. By then it's basically too late to do anything except hope.

The Reactive Version, Which Is What Most of Us Actually Do

The reactive approach looks like this: watch the forecast, notice the tree looks concerning the day before a storm, maybe move the car to the other side of the driveway, and wait it out. If something comes down, deal with the cleanup and the insurance call afterward. This isn't really preparation, it's just noticing the risk exists at the last possible moment when there's nothing left to do about it.

I did this myself for years. It wasn't laziness exactly, it just never occurred to me that there was a "before" version of this that involved anything more than hoping.

The Proactive Version, Which I Only Started Doing Recently

The proactive version means having someone actually look at your big trees in the fall, before the ground freezes and before the first real storm system of the season, specifically for the kind of structural issues that don't show up from casual observation. Things like a co-dominant trunk split, deadwood in the upper canopy, or root zone drainage problems. These are the traits that actually predict whether a given tree handles a winter storm fine or doesn't, and none of them are things you can meaningfully assess by looking up nervously the night before a nor'easter.

I had this done on my own property for the first time last fall, mostly prompted by a neighbor's tree coming down the winter before. a local arborist walked the yard, flagged some deadwood I hadn't noticed over a section of fence, and pointed out a trunk split on one of my oaks that's apparently worth monitoring, though not urgent enough to need cabling yet.

The Difference in What You Can Actually Do

The practical gap between these two approaches is enormous. In the reactive version, your options the night before a storm are basically limited to hoping and maybe moving a car. In the proactive version, done weeks or months ahead, your options include actual pruning, cabling for a weak union, addressing a drainage issue near the root zone, or in some cases deciding a specific tree needs to come down entirely rather than risk it. All of those things take time to schedule and, in some cases, require dry ground and decent weather to do safely, which a day-before-the-storm timeline simply doesn't allow.

Why This Is Especially True for Oaks Specifically

Oaks seem to be the species that catches people off guard most, since a big old oak often looks like the sturdiest thing in the yard right up until a storm finds the specific structural weakness it has. Both Hufnagel Tree and Middletown Tree Service work with homeowners across Monmouth County on this kind of fall assessment specifically because oaks are so common here and the structural issues that matter are rarely obvious without someone trained to look for them.

What Changed for Me

I'm not going to pretend I have this fully figured out, but I've stopped being someone who checks the forecast the day before a storm and looks nervously at my trees for the first time that season. The Rutgers Cooperative Extension has some good general reading on this if you want the background before making any calls, and the National Weather Service is still where I check the actual forecast, but the tree assessment itself happens in October now, not the night before a storm watch gets issued.

The Part I Didn't Expect: It's Not a One-Time Thing

I assumed, going into last fall's assessment, that I'd get a report, fix whatever needed fixing, and be done with the question for good. That's not really how it works. The arborist was clear that the trunk split on my oak is something to keep an eye on over time, not a problem that gets solved once and forgotten. Trees keep growing and conditions keep changing, so what was a minor concern last year could look different in two or three years, especially after a rough summer or if something changes in the surrounding soil or grading.

That reframed the whole thing for me. It's less "get this checked once" and more "start a relationship with someone who knows your trees," similar to how you'd think about a dentist rather than a one-time repair. I don't love the idea of an ongoing cost, but I also don't love the idea of the alternative, which is going back to not knowing anything about the actual condition of trees that are big enough to seriously damage my house if something goes wrong.

What I'd Say to Someone Who Thinks This Sounds Excessive

I get it, because I used to think this way myself. It can feel like a lot of attention for trees that have been fine for decades. But the entire reason this matters is that "fine for decades" and "structurally sound" aren't the same claim, and the only way to actually know which one applies to your trees is to have someone qualified look. It doesn't have to be an annual production. Even getting a baseline assessment done once, and then a shorter follow-up look every few years, puts you in a completely different position than never having looked at all. The night-before-the-storm version of tree awareness isn't really awareness. It's just noticing the risk existed right when it's too late to act on it.

One More Thing I'd Add

If you take nothing else from this, take the timing point. The single biggest difference between the reactive version and the proactive version isn't the quality of information available, plenty of people who wait until the night before a storm know, in a general sense, that old trees can be risky. The difference is entirely about when you find out something specific about your own trees relative to when you'd still have options if the answer isn't good. Fall, before the ground freezes, is when you actually have options. The night a storm watch gets issued, you don't, no matter how much you suddenly want to do something about it. I wish someone had put it to me in exactly those terms years ago, instead of leaving me to figure it out only after watching a neighbor's tree come down and hoping the lesson wasn't going to come at my own expense first.

What I'm Doing Differently This Fall

This year I'm not waiting for a prompt from a neighbor's bad luck to get the follow-up look scheduled. I put a reminder on my calendar for early October, both for my own trees and to check in with a couple of neighbors who've mentioned wanting to do the same thing but haven't gotten around to it. It's a small thing, a calendar reminder isn't exactly a heroic act of tree stewardship, but it's the difference between this happening on a predictable schedule versus happening reactively after something on the street reminds everyone that old trees exist and sometimes fail.

Last winter's second nor'easter took down a huge oak two doors from me. Not a dead-looking tree, not something anyone on the street had flagged as a problem. A big, healthy-looking oak that had been there longer than any of our houses. It came down across the side yard sometime overnight, missed the house by maybe fifteen feet, and took a section of fence with it.

I remember standing out there the next morning with a couple of other neighbors, all of us saying some version of the same thing. We had no idea that tree was a risk. It looked completely fine.

What I Learned Afterward

The homeowner had someone come out to look at it after the fact, mostly to deal with the cleanup, and mentioned something that stuck with me. Apparently the tree had what's called a co-dominant trunk, basically two large trunks splitting from close to the same spot instead of one main trunk, and that kind of split is a known weak point that doesn't necessarily show from the outside. It's not something you'd notice walking past a tree every day for years. It's something a professional looks for specifically.

That was the first time I understood that "looks healthy" and "structurally sound" are not the same question, and a tree can be fully green and full and fine-looking every summer while still carrying a structural issue that only becomes obvious when a winter storm actually tests it.

Looking at My Own Yard Differently

I have two large oaks in my own yard, both older than the house based on what the previous owner told us. After that nor'easter, I started actually looking at them instead of just appreciating the shade. One of them, I'm pretty sure, has the same kind of split trunk situation. I genuinely don't know if that means anything or not. I'm not qualified to make that call, and that's exactly the point.

I ended up reaching out to a couple of tree companies in the area, mostly to get a sense of what an actual assessment involves and what it costs. Hufnagel Tree came out and walked the property with me, looked at both oaks, checked the trunk split I'd noticed along with a few other things I wouldn't have thought to look at, drainage around the base, some deadwood higher up in the canopy I hadn't even clocked from the ground. Turned out one of the oaks had a section of dead branches over the driveway that needed to come out regardless of the trunk question.

What Surprised Me About the Whole Process

I expected to be told either "it's fine" or "it needs to come down," and the actual answer was more specific than that. The tree with the split trunk is apparently a reasonable candidate for cabling, which is a support system installed between the two trunks to limit how much they can move independently in wind. It's not a guarantee of anything, but it's a real intervention, not just a wait-and-see.

Middletown Tree Service also works in this area and does similar assessments if you're closer to that side of the county. The point isn't which company, it's that this kind of assessment exists and most of us have never had one done on trees we've lived with for years.

What I'd Tell Anyone With Big Old Trees

If you have a mature tree you've never had specifically assessed, and especially if it has any visible trunk split or a lean you've gotten used to not noticing, get it looked at before winter, not after a storm makes the decision for you. The Rutgers Cooperative Extension has some genuinely useful material on what makes older trees more storm-prone if you want to understand the reasoning before you call anyone, and the International Society of Arboriculture keeps a searchable directory if you want to verify someone's credentials before letting them near a big tree.

The tree that came down two doors from me missed the house. I don't think about that as lucky anymore. I think about it as a specific structural issue that nobody happened to catch in time, on a tree that looked completely fine right up until it didn't.

What the Cleanup Actually Looked Like

I should say something about what the aftermath actually involved, because I think people picture a fallen tree as a weekend chainsaw job and it really isn't, not for something that size. The homeowner had to deal with an insurance claim, a crew to remove the fence section and clear the downed wood, and a stump that's still sitting there because grinding it out was a separate cost nobody had budgeted for. The whole process took a couple of months from the storm to the yard actually looking normal again. None of that compares to what could have happened if the tree had landed fifteen feet the other direction, but it was still a genuinely disruptive few months for a family that didn't do anything wrong, they just had an old tree with a hidden structural issue.

Why I Didn't Just Assume My Trees Were Fine

Part of what pushed me to actually get my own trees looked at, instead of just feeling vaguely more aware, was realizing that "we've never had a problem" isn't the same as "there's no problem." My oaks have been standing through plenty of storms already. That's reassuring in one sense, but survivorship isn't the same as a clean bill of structural health, especially for a defect like a co-dominant trunk that can sit there for decades before a particular combination of ice load and wind finally finds it.

Talking to My Neighbors About It

A few of us on the street have since talked about doing this more collectively, comparing notes on which of our trees have been looked at and which haven't, mostly because a handful of the older oaks on this block were probably planted around the same time by whoever developed the street originally. If one tree from that era has a structural issue, it's not unreasonable to wonder whether others nearby might share whatever growing conditions produced it. I don't know if that theory holds up, but it's made the conversation feel less like an individual homeowner problem and more like a shared thing worth being informed about as a block.

Where I Landed on the Whole Thing

I ended up scheduling the cabling on my oak with the split trunk, mostly because the cost was reasonable relative to what a failure could mean, and because I'd rather know I did something than spend every windy night wondering. The other oak checked out fine, no split, no significant deadwood, nothing flagged. I'm not treating that as a permanent clean bill of health, more as this year's answer, and I'll probably have both trees looked at again in a couple of years rather than assuming nothing changes.

Portland has other ideas.

In many cases, removing a tree that's 12 inches or more in diameter requires a permit, even if it's on your own property.

Ignore the rules, and the consequences can be expensive.

One homeowner who removed a 24-inch tree without a permit was fined $24,000.

Some trees are protected even more.

Heritage Trees can require approval before they're even pruned.

And if a tree is an emergency? You can remove it first but you'll still need to document why afterward.

Turns out, owning the land doesn't always mean you get the final say.

There are two mature ash trees three houses apart on our block. One still has a full, healthy looking canopy. The other lost most of its top branches this spring and has visible bark damage low on the trunk. Same species, similar age based on trunk diameter, similar sun exposure, and as far as anyone can tell, similar soil. For a while I genuinely could not figure out why one was thriving and the other was clearly dying of the same thing.

The Question That Kept Bothering Me

It is the kind of question that seems like it should have a simple answer. Same species, same general conditions, same neighborhood presumably exposed to the same regional emerald ash borer population. Why would one tree be functionally fine while another, thirty yards away, is falling apart. I started paying more attention to both trees and asking around, and the answer turned out to be less about any single factor and more about several smaller differences stacking up.

Timing of Infestation Isn't Uniform

The first thing I learned is that even within a small area, individual trees do not all get infested at the same time. Adult beetles disperse somewhat randomly, and a tree that happened to get colonized two or three years before its neighbor is going to look much worse right now, even if the neighboring tree ends up following the exact same trajectory eventually. The healthier looking tree on our block might just be a year or two behind, not permanently immune.

Prior Stress Makes a Real Difference

The second factor, which took longer to figure out, is that the declining tree had a rough few years before anyone even suspected emerald ash borer. There was construction on an adjacent lot about four years ago that disturbed some of the root zone, and the tree never fully recovered its vigor afterward. A tree already dealing with root stress has less capacity to withstand additional pressure from insect feeding, compared to a tree that went into the infestation at full health and vigor.

The healthier tree, as far as anyone remembers, has had a pretty uneventful history. No nearby construction, no drought stress that anyone noticed, nothing unusual. It went into whatever exposure it's had to emerald ash borer with more physiological reserve to draw on.

Genetic Variation Might Play a Role Too

I read that individual trees within the same species can have some natural variation in resistance or vigor, even among trees that look similar from the outside. This is harder to verify without actual testing, but it's a plausible piece of the puzzle. Not every ash tree responds identically to the same level of insect pressure, the same way not every person responds identically to the same virus.

Location Relative to Other Ash Trees Matters

The declining tree sits closer to a cluster of ash trees a couple of streets over that were removed a year or two back after they were confirmed infested. It's plausible that beetle activity concentrated more heavily in that immediate area before those trees came down, putting extra pressure on nearby ash trees, including ours, during that window. The healthier tree on our block is a bit further from that cluster, which might mean it simply saw less concentrated exposure during the period when local beetle populations were at their highest.

What This Means for How We Think About Risk

The lesson I took away from comparing these two trees is that "my neighbor's ash tree looks fine so mine probably will too" and "my neighbor's ash tree is dying so mine definitely will too" are both bad assumptions. Individual tree history, prior stress, proximity to other infested trees, and probably some amount of natural variation all combine in ways that are hard to predict from the outside. The only way to actually know how your specific tree is doing is to check it directly rather than using a neighboring tree as a stand-in.

Checking Our Own Tree With This in Mind

We have one ash tree in our own yard, and after seeing how differently two similar looking trees three houses apart can turn out, I went and checked ours carefully rather than assuming it was fine because it looked reasonably full from a distance. I found a little bit of blonding on one limb, nothing dramatic, but enough to make me want to keep an eye on it going forward rather than assuming it's in the clear just because it's not in obvious decline yet.

Where I Went for More Information

The USDA Animal and Plant Health Inspection Service at aphis.usda.gov has useful background on how emerald ash borer disperses and why local infestation intensity can vary block to block rather than spreading in a perfectly uniform way. That helped explain some of what we were seeing on our own street. The Rutgers New Jersey Agricultural Experiment Station at njaes.rutgers.edu also has New Jersey specific guidance that was useful for understanding typical progression timelines in our region specifically.

What I'd Tell Anyone Comparing Trees Like We Did

If you have ash trees near neighbors' trees that look noticeably different in condition, it is worth resisting the urge to draw a simple conclusion either way. A neighbor's healthy tree does not mean yours is safe, and a neighbor's declining tree does not mean yours is doomed. Prior stress, timing of exposure, and proximity to other infested trees all matter more than most people assume, and the only reliable way to know your own tree's actual status is checking it directly.

We are planning to have someone from Middletown tree care take a look at ours this season, partly because of the blonding I found and partly because I would rather get an actual professional read now than wait and find out later that the timing window for treatment had already closed. The neighbor with the more advanced decline mentioned they'd reached out to Hufnagel Tree as well, since their tree is far enough along that they wanted a second opinion on whether treatment still made sense or whether removal was the more realistic path at this point.

Something Else I Noticed Once I Started Comparing

Once I started actually paying attention to these two trees instead of just noticing them in passing, I realized how much my own assumptions had been shaped by whichever tree I happened to look at most recently. On days I walked past the declining tree first, I found myself assuming the whole block's ash trees were probably in trouble. On days I passed the healthier one first, I felt reassured in a way that wasn't really justified either. Neither reaction was based on anything except which tree happened to be more visible on a given walk, which is a pretty flimsy basis for actually judging risk.

That is part of why I think direct inspection matters so much more than general impressions. It is easy to let whichever tree you happen to notice most shape your sense of how things are going overall, when the reality is that each tree's situation depends on its own specific history, not on being averaged in with whatever else is visible nearby.

What I'd Do Differently If I Were Starting Over

If I were doing this again from the beginning, I would have started checking both trees, and probably a few more on the block, much earlier rather than waiting until the visible difference between them became impossible to ignore. By the time I started paying close attention, the declining tree already had exit holes and significant canopy loss, which likely meant the window for treatment being genuinely effective had already narrowed considerably. Catching that kind of divergence a season or two earlier, before the visible gap between two similar trees becomes dramatic, would have given whoever owns that tree more options than they probably have now.

The Bigger Picture