Rotary rock picker invented by Minnesota man

Kent Rosessler stands by his invention, the Robo, a rotary rock picker that mounts to any skid loader.

The world’s first rotary rock picker for a skid loader was invented by a Minnesota man, Kent Rosessler.

Kent and his son, Ryan, have been farming and picking rocks for years by hand and using a rock bucket.

One day Ryan told Kent, “We should build a rotary rock picker like our rotary combine” and the pair have been planning ever since. They named the rock picker “Robo” because Ryan said “it picks rocks like a robot” and it reminds him of playing Pac-Man, a video game.

The rotary rock picker is a drum style and follows the concept of a rotary combine. It mounts to any skid loader and Kent says “Robo will pick two to three times faster than a rock bucket and hold three times more rocks. The main benefit is you get clean rocks even in heavy trash fields.”

The two have been selling the rocks to landscapers and contractors who want clean rocks with no dirt (as required by law for use as rip-rap for shorelines and storm pipes).

With most stone piles picked with a rock bucket or pull type picker, too much dirt goes to the stone pile and mother nature can only wash off the top rocks leaving everything below dirty. “With Robo our rock piles are clean to the bottom, and we get paid a premium” said Kent.

Kent said, “We disk rip our corn fields in the fall and start picking up until frost sets in. With heavy trash in corn stalks or sod all you do is scoop the rocks with the dirt and debris, spin the drum and everything is gone except the rocks.”

Kent said, “What we don’t get picked in fall we can pick early spring because with Robo you can scoop the wet dirt and rocks, spin the drum and the rocks are picked clean. We get three to four more weeks of picking time than everyone else.

“A farmer does not want to be picking rock when he is supposed to be planting.” Kent also said. “We have had a prototype in testing for the last two years. We have all the bugs worked out. The machine is bullet proof. It should last the average farmer a lifetime.”

Kent has filed for a patent with the U.S. Patent Office. The dealers that have Robo on their showroom floors are Arnolds Case-IH of St. Cloud, Lake Henry Equipment of Pierz, Evergreen John Deere Dealership, Little Falls and Timmer Implement of Pease. “We did have a booth at Farm Fest and Big Iron Show in Fargo where we sold quite a few units.” List price is $4,995 and can be seen online at

Ryan likes to pick rocks now, he said, because “it is fast and easy.”