A downtown tree replacement program still is an acorn at this point while the city investigates just what sort of trees will work best in the area.
City Manager Larry Lehman said the difficulty is in finding trees that don't attract birds, don't produce fruit, don't grow too tall and don't have roots that grow out.
Not exactly easy criteria to match. The city has dealt or deals with those issues when it comes to trees.
Simply put, Lehman said it's "finding that proper tree."
Lehman said the city has received a number of complaints about problems associated with trees, including from businesses where trees block signs to portions of Main Street that lack trees.
Even so, Lehman said trees play a valuable role in downtown health. Aside from breaking up the appearance of concrete and glass, he said there are studies that show trees keep people in downtown areas - that means more commerce.
Lehman also speculated the Urban Renewal Agency would pay for a contractor to remove downtown trees and plant replacements.
Town & Country Tree Service removed some downtown trees a couple of years ago. Owner Larry Moore estimated it could cost about $100 to $125 per tree for removal, but added it may cost more to put in new trees.
Moore explained costs depend on the size of the tree and therefore the amount of labor involved. Additionally, there's an irrigation system for each tree to consider.
Moore said a type of flowering crab apple tree called spring snow grow is in downtown now. Those are fine trees, he said, when they grow in the right place.
"But that's the wrong place," he said.
That's because the city has trimmed the trees to grow tall and narrow, which isn't the species' natural inclination.
These are issues others cities have dealt with.
Jim Dumont is the parks and recreation director for Walla Walla. He explained any tree plan needs to consider what type of trees to plant and what purpose the trees will serve.
For Walla Walla, the goal is to create a canopy. But meeting that goal means designing the area to be compatible with trees.
"And hopefully you reduce amount of impact to infrastructure," he said.
Pendleton and Walla Walla have used underground metal barriers to inhibit root systems from disrupting waterlines and ruining sidewalks, but Dumont said that sort of plan isn't entirely successful.
Dumont said structural soil - a combination of rock and silt - has become a popular choice for cities to control the direction of roots
Structural soil allows roots to grow between the rocks and through the silt, while at the same time providing support for surfaces, such as sidewalks.
No matter what actions a city considers, trees always interfere with electrical and irrigation systems. But, Dumont said, considering what trees bring to a downtown area, the hassle is worth it.