What Does It Cost to Treat an Ash Tree for Emerald Ash Borer in Rochester?

By Linda Marsh, Pests & Diseases. Last updated: July 22, 2026

If you still have a mature ash standing in your Pittsford or Greece yard, you already know emerald ash borer (EAB) is the reason it might not stay standing. What most price guides skip is that saving it is not one bill you pay and forget. It is a repeating cost tied to the size of your tree. This piece puts sourced dollar logic on both paths, treatment on a cycle versus a one-time removal, so you can run your own math before you call anyone. If you are still deciding whether to save the tree at all, our companion guide on whether an EAB-infested ash is worth saving walks the decision itself; this one is about the money.

How is emerald ash borer treatment priced?

Professional EAB treatment is priced per inch of trunk diameter, measured as DBH (diameter at breast height), because the insecticide dose scales with tree size. A slender ornamental ash costs far less per visit than a broad mature shade ash. The most effective delivery is a trunk injection of emamectin benzoate applied by a licensed applicator, not a weaker do-it-yourself soil drench.

Because the dose tracks trunk size, University of Wisconsin-Madison Extension notes plainly that "larger trees will require a larger amount of product and costs will be higher." That is why a big tree is never a bargain to protect. On the homeowner side, Michigan State University Extension prices soil-drench product by trunk measurement (roughly one ounce of imidacloprid per inch of trunk circumference) but cautions those products "are not recommended for trees with a trunk dbh of greater than 15 inches," which is exactly the size of tree most people want to save. For arborist-applied treatment, Wisconsin Extension puts the ballpark at "$200 or more" depending on tree size, insecticide, and method. The takeaway: ask any quote to break the price out per inch of DBH so you can compare two bids on the same tree.

How often do you have to re-treat, and for how long?

Emamectin benzoate trunk injections protect an ash for about two years, so the tree has to be re-treated roughly every other year for as long as you want to keep it. Emerald ash borer pressure across Monroe County does not fade on its own, which is why treatment is a standing line in the budget rather than a single invoice you clear once and forget.

Wisconsin Extension is specific: emamectin benzoate products "are labeled for two years of protection" and "can effectively protect an ash tree if the tree is treated every other year." Weaker homeowner soil drenches, by contrast, "require yearly applications," so they cost less per visit but come due twice as often. Either way, the honest number is not the price of one treatment. It is the price of one treatment multiplied by the treatments you will buy over the next decade. Because the infestation is entrenched here, plan on that cadence continuing; our overview of emerald ash borer in Monroe County explains why the local pressure is not letting up.

How does treatment cost compare to removal and replacement?

Treatment is a smaller recurring bill; removal is a larger one-time cost that climbs with size and proximity to your house. Wisconsin Extension notes a small ash under 25 feet "may cost several hundred dollars to be removed," while "larger trees may cost $1,000 or more." Removal also erases mature shade that a replacement sapling needs more than a decade to rebuild, a cost that never shows up on the invoice.

The fair comparison is over a 10-year horizon, not a single year. Stack five or so injection cycles against one removal plus a young replacement, and for a large, healthy shade ash the recurring treatment frequently comes in lower once you count the lost canopy. There is also a timing trap: an EAB-killed ash dries out and turns brittle fast, which makes it more dangerous and more expensive to take down later, often pushing crews toward slower crane or bucket work. Waiting for the tree to die rarely saves money. For current local removal figures, see our breakdown of tree removal cost in Rochester, NY.

When does treating an ash pencil out financially?

Treatment pencils out for a structurally sound, well-placed, high-value ash caught before heavy canopy loss, where years of preserved shade and curb appeal outweigh an injection every other year. It rarely pays for a small, poorly placed, or already-declining tree, where a lifetime of treatments costs more than the tree returns in shade or property value.

Michigan State University Extension advises that treatment "should begin when trees are healthy," and warns that "failures to save ash trees with this treatment are most likely to occur with large trees growing in dry soils." In other words, the ideal candidate is a valued tree you protect proactively, not one you rescue late. Confirming which category your ash falls into is exactly the judgment an ISA Certified Arborist provides, and it is part of what a proper plant health care program checks before recommending a spend.

Is it too late, and too costly, to treat your ash tree?

Once an ash has lost more than about half its canopy, treatment is no longer recommended, and the money is better spent on removal. Past that point the tree's vascular system cannot move insecticide reliably, so you would be paying full price for a treatment unlikely to work. Below that line, the odds tilt strongly back toward saving the tree.

University of Wisconsin-Madison Extension states the threshold directly: "Insecticide treatments are not recommended for trees with greater than 50% canopy thinning; these trees should be removed." Walk out in midsummer with the leaves fully out and look up: heavy dieback at the top of the crown, bare branch tips, and woodpecker flecking on the bark are signs decline has advanced. If the canopy is still mostly full, treatment is a live option worth pricing. If it is thinner than half, spending on injections usually just delays a removal you will pay for anyway. The decision framework in our treat-versus-remove cost guide walks that judgment in more detail.

FAQ

How much does one EAB treatment cost?

It depends on trunk diameter, because the dose scales with DBH. University of Wisconsin-Madison Extension puts arborist-applied treatment at "$200 or more," with the exact figure driven by tree size, the insecticide chosen, and the application method. Ask for the price per inch of DBH so you can compare bids on the same tree.

How many years do I have to keep treating?

For as long as you want to keep the tree. Emamectin benzoate injections protect for about two years, so plan on re-treating roughly every other year indefinitely. EAB pressure in Monroe County does not disappear, so treatment is an ongoing commitment rather than a one-time fix.

Is a cheaper soil drench as good as a trunk injection?

Usually not for a large tree. Homeowner soil drenches cost less per application but require yearly treatment and, per Michigan State University Extension, are "not recommended for trees with a trunk dbh of greater than 15 inches." Arborists favor emamectin benzoate trunk injection for trees actually worth saving.

Can a heavily infested ash still be saved?

Often not economically. Once canopy thinning passes about 50 percent, University of Wisconsin-Madison Extension recommends removal rather than treatment, because the tree can no longer distribute the insecticide reliably. Below that threshold, a healthy, well-placed ash is a strong treatment candidate.

Is EAB treatment cheaper than removal?

For a large, healthy, well-placed ash, treatment is frequently cheaper over a 10-year horizon once you count the value of preserved shade and the rising cost of removing a dead, brittle tree later. For a small or declining ash, a one-time removal usually wins.

Sources

• Monster Tree Service of Rochester
• University of Wisconsin-Madison Extension: Is My Ash Tree Worth Treating for Emerald Ash Borer?
• Michigan State University Extension: Emerald ash borer treatments for homeowners
• Cornell Cooperative Extension: Emerald Ash Borer
• NYS Department of Environmental Conservation: Emerald Ash Borer (EAB)