ST. PAUL, Minn. (AP) — Minnesota agriculture officials are encouraged by the initial results of a new way to find emerald ash borers.

The Minnesota Department of Agriculture recently finished the first year of a three-year study to detect the destructive tree pest.

Researchers sampled branches from 300 trees in the original Minnesota infestation area in St. Paul and up to four kilometers away.

Twenty of the 300 sampled trees were found to be infested with emerald ash borer. Of those 20 trees, only one was outside the core infestation.

Scientists say they found fewer infested trees than expected. And, there were low numbers of the beetles in the infested trees.

An official says that’s likely due to efforts to remove and destroy infested trees in Minneapolis and St. Paul.

(© Copyright 2012 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)