Chip Chat With Rotochopper 

October 1, 2026

Since its first paper chopper hit the market in 1990, Rotochopper has helped drive major advancements in fiber processing. Over the past 35 years, the wood recycling industry has grown through both regulation changes and consumer demand for high-quality landscape products. Mulch Matters spoke with Rotochopper about industry trends in grinding wood waste. 

WHAT TRENDS ARE YOU SEEING ACROSS THE INDUSTRY? 

ROTOCHOPPER: 

Nationwide, the bark and wood waste from sawmill operations, called hog fuel, has traditionally gone to mill boiler fuel. Mills across the country are converting their wood-burning boilers to natural gas, so in a lot of areas that material has nowhere to go. We’re seeing some mulch operations take that material and color it. There isn’t much work to get from one to the other. Boiler fuel is already about three-inch minus, and most colored mulch is two-inch minus. It runs fast and it’s easy on teeth and screens. 

That’s the opportunity more broadly. There’s material sitting in a lot of places that somebody is paying to get rid of. Ground and colored, that same material is something you sell. The producers doing well right now are the ones who looked around at what’s near them instead of at what they’ve always run. 

HOW DOES AN OPERATION SETTLE ON ITS IDEAL PARTICLE SIZE? 

ROTOCHOPPER: 

Moisture content really drives particle size. Regions that have a lot of annual precipitation tend to grind larger chips to avoid plugging and burning more fuel. There are also different factors in handling fines. Some of that is driven by the market and some by the size of the operation. 

Many smaller operations (under 5,000 yards) utilize every bit of their material to produce colored mulch, so they leave the fines in the material. Larger operations — especially getting into the bagged market — tend to remove the fines.  

For compost operations that get into colored mulch, they often incorporate their overs and color them because the material would be too large to break down. So, the colored mulch product is going to be a larger particle size. 

HOW DO YOUR MACHINES TACKLE CONSISTENCY IN PARTICLE SIZE? 

ROTOCHOPPER: 

At its simplest, a grinder is built to make big wood small. Getting the size you need and holding it there across the grind comes down to a few things. 

Everything starts with the feed. Our machines watch the torque on the rotor and adjust the feed so material reaches the grinding chamber at a rate the rotor can keep up with and not plug. We also have a gapless belt-to-chamber transition, so nothing goes unground. 

From there, the screen setup is really where size is policed. Operators run the screens and teeth that fit their feedstock and the product they’re selling, and change them fast when either one changes. Nothing leaves the chamber without going through the screen, and baffles catch any spears, those slivers that would otherwise slip through end-first and wind up in the pile. 

Why do these features matter? Because they let the operator focus on what they do best: keeping the hopper full and moving product through.