emerald ash borer

Here’s an update from the front lines:

Tree removal: The city has removed about 3,000 of the 14,000 public ash trees that line Lincoln’s streets and are scattered throughout its parks and golf courses — including 360 so far this fiscal year.

It’s fallen more than 100 trees short of its goal of removing 800 public ash trees annually the past couple of years, but its forestry crew was still busy.

For instance, in 2020, it faced a half-dozen back-to-back storms that did significant damage to all types of city trees, not just ash.

“And we spent a lot of time doing cleanup that year,” said Lynn Johnson, director of the city Parks and Recreation Department. “When that happens, it’s all hands on deck.”

The city normally removes 800 non-ash trees per year; in 2020, it removed nearly 1,800.

Treatment: The city saw the Asian insect coming. After it was detected in North America in the early 2000s, it started marching west, killing tens of millions of ash trees.

Lincoln drew a hard line at first, planning to remove every public ash tree in its city limits.

But it added a second strategy a couple of years ago, and began treating its trees with a chemical that can prolong their lives.

It set a goal of treating 1,700 eligible trees a year. Those getting stays of executions must be viable — relatively young but big and strong — or in significant locations, like the five towering trees that shade Witherbee Park near 46th and O streets, or the autumn purple ash that line a stretch of Goodhue Boulevard south of the Capitol.

The city plans to treat the trees every three years, allowing it eventually to extend the life of about 5,000 trees that otherwise would have been cut down.

During its first-year pilot program, it treated about 350. Last fiscal year, it treated 1,349.

The city is also continuing its Adopt-An-Ash Program, which allows homeowners to privately treat eligible public trees along the street in front of their homes. But it wants to know who’s helping so it doesn’t inadvertently cut down a treated tree. Learn more by going to trees.lincoln.ne.gov and clicking on Adopt-An-Ash Program.

The replacements: The city plans to replace each ash it takes out, and offers vouchers to homeowners to pick out and plant an approved species.

It worked two years ago, when more than 800 replacement trees were planted. But last fiscal year, just 237 were replaced.

And they’re learning that number hinges on the socioeconomic status of a neighborhood. Higher-rental and lower-income areas have been less likely to replace the ash trees the city removes, he said.

“Landlords don’t tend to use the vouchers, and if someone’s working two to three jobs, they’ve already got their plate full.”

To change that, his department recently hired a new community forestry planner, who will work with landlords and neighborhood associations — but also coordinate the contracting of the planting where it’s not done voluntarily.

Time taking its toll: And finally, ash borers take some time to kill their hosts, and now that they’ve been busy for a few years, city crews are starting to see more signs and symptoms of damage.

“We’re getting to that point on the curve where we’ll probably see a significant uptick in the number of trees dying.”

Every ash on the map: Finally, the city has plotted every public ash on a searchable map, including those under treatment, and those already removed. To find out if the tree in front of your house is an ash, go to trees.lincoln.ne.gov, click Adopt-An-Ash Program, and then click Public Ash Trees.