Charlie Brown's kite-eating tree is getting more aggressive.

Duluth's Natural Resources Research Institute lost its drone in Hartley Park last week and is offering a $100 reward for its return.

"It was mapping vegetation and was coming in to land on Soapbox Hill when it veered off to the southeast," an online have-you-seen-this-drone flyer says. A map shows it is believed to be somewhere between trails south of the Nature Center.

The drone is black with yellow highlights and has about a 3-foot wingspan. Email knixon@d.umn.edu or ghost@d.umn.edu if found or for more information.