Salt Lake City officials are desperately trying to figure out how to correct an employee error that killed more than 200 trees along the North Temple corridor on the west side of the building this year, but a permanent solution will be years away.

After staff accidentally used an herbicide late last year that killed 219 trees along West Side Street and elsewhere in the city, experts advised the city to wait three years before replacing the dead trees, a new city memo said.

The Department of Public Lands plans to tell the Salt Lake City Council on Tuesday that it will begin planting replacement trees in fall 2026, assuming soil tests are positive.

While the delay may not be welcome news for a neighborhood whose treetops pale in comparison to the city’s more affluent east side, the city said it is determined to make up for its mistake.

“Many trees are being replaced along the North Temple Corridor. In addition, the department has committed to planting two new trees for every tree lost due to inadvertent herbicide use,” the city wrote in its memo. “Public Lands staff are locating suitable new planting sites in the North Temple area and will inform the community once these new locations are determined.”

Public Lands will purchase 100 planters and plant trees as an interim solution while the city waits for the toxic threat to pass. The trees will then be replanted in late 2026 when the soil is deemed safe enough.

A city worker applied an herbicide normally used to kill shrubs and trees while keeping nearby grass alive. The city admitted this year that the worker had sprayed the agent near the bases of hundreds of trees to kill weeds.

During this year’s growing season, the error became apparent as hundreds of trees failed to produce leaves.

The city tried in vain to protect the affected trees by over-watering them to flush out the herbicides.

“As a result, 219 trees have died. Industry experts have advised us to wait three years before planting new trees to prevent active herbicides remaining in the soil from negatively impacting future tree plantings,” the city wrote.

The city said it has revised its protocols to prevent similar accidents in the future, including a new “double-safe procedure” that requires licensed personnel to get approval from a supervisor and a warehouse technician before applying herbicides.

The City Council is considering approving a $505,000 budget amendment to remove dead trees and four inches of contaminated soil and purchase planters.

Construction of Salt Lake asked the city what types of trees it plans to plant in October 2026 and for more details on where the trees will be planted.

This post may be updated.

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