PIERRE, S.D. (AP) — The South Dakota Department of Agriculture says landowners who had their pine trees sprayed this year to protect them from mountain pine beetles have noted that trees are still getting lost.

State forester Ray Sowers says some landowners that had dozens to hundreds of trees sprayed by commercial services have reported tree losses from mountain pine beetle attack at anywhere from 20 to 60 percent or more.

That's much higher than what the department has seen in the past.

A normal loss from spraying is anywhere from 0 percent to 3 percent.

Pine trees are sprayed in the spring and early summer to protect the tree from attack by the mountain pine beetle. They're preventative measures, as once beetles infest a tree there are no treatments that can save it.

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