LINCOLN, Neb. (AP) – Lincoln officials are blaming drought stress for the deaths of more than 550 trees in Pioneers Park.

Most of them were mature white pines, planted 20 to 40 years ago.

The Lincoln Journal Star reports (http://bit.ly/Pu0WWf) that there were fears the trees had fallen victim to the pine wilt that’s been killing Scotch pines and some other pine species. White pines are generally thought to be resistant to pine wilt.

But officials have determined the trees died from drought stress.

The trees are being removed. Many likely will be replaced in spring during a volunteer planting event.