Tub grinders, horizontal grinders, whole-tree chippers, and other mechanical giants can turn an entire tree into toothpick-size particles in a matter of seconds.

By Mark Saunders

A Little Bit of History
Turning Dirt Into Soil
Innovations Abound

The behemoth machines that have created a new era of recycling and completely mushroomed the compost and mulch industries have only been in their current format over the last 10-20 years. Developed, for the most part, from an application that was designed to make it easier for ranchers to feed their cattle, this application of a technology designed for a different industry has made much of the mulch and compost boom possible.

A Little Bit of History

W.H.O. Manufacturing of Lamar, CO, built the first tub grinder in 1947. Originally this equipment was designed for grinding hay and other agricultural material so it was more efficient to feed it to cows. True, hay busters are valuable tools for farmers and ranchers, but the recent boom in grinders used for environmental purposes has little or nothing to do with the amount of alfalfa grown in the United States or the exponential increase in buffalo ranching in Montana. No, something happened between 1970 and 1990 that gave new life to the tub-grinder industry and spawned a revolution in new equipment designed to pulverize such bulky material as tree stumps, brush, pallets, and other forms of greenwaste once destined to be burned "out back" or hauled off to the nearest dump. Increased immigration coupled with medical technology’s gift of longer life helped the population in the US soar to new heights in the latter part of the 20^th century. And the numbers from the 2000 census clearly confirm that this growing trend shows no signs of slowing down any time soon. With that dramatic rise in population, especially in in-vogue states such as California, Nevada, and Colorado, the local infrastructures were ill-equipped to handle the massive migration of new residents that made the relocation of the Joads in the 1930s look like a road show at the local Hilton. As the population soared, hundreds of density-related infrastructure problems reared their ugly little heads. Along with congested highways, increasing air pollution, underplanned developments, inadequate waterworks, and insufficient power grids came the problem of what to do with all the trash these new residents were creating–specifically, how do you cut down on the limited landfill space available without creating more air pollution? In other words, you can’t burn it or bury it, so you need to come up with a better alternative. One of the obvious answers was to recycle such materials as glass, plastic, aluminum, cardboard, and newspapers that virtually every household produces every day. Another tact was to tackle the big, bulky organic matter that added unnecessary volume to the landfill mix. You don’t need an advanced degree in solid waste management to realize that trees, limbs, brush, root balls, stumps, grass, and other yardwaste take up a lot of space in a landfill. What happened was a marriage between two low-tech applications: the centuries-old tradition of composting and the relatively new concept of hay busting.

Turning Dirt Into Soil

This union was another interesting offshoot of the 1960s counterculture revolution: Large-equipment manufacturers, such as W.H.O., found a new niche and created a large-scale compost consciousness that has altered the way America thinks about making plants grow in the backyard. Using farming strategies that fell out of favor with the advent of potent petrochemical fertilizers, progressive entrepreneurs found ways to use these hay-busting tub grinders to add organic carbon sources (wood, agricultural byproducts, and yard clippings) to animal manure, grass, and other nitrogen sources to create soil enhancers that outperform expensive petrochemical products. Not only did this next step in the world of recycling keep the trees and yardwaste out of landfills, making municipalities and trash haulers very happy, it also created a very profitable industry for those with the financial wherewithal to buy or lease some major equipment.

Take a trip to any Walgreens or Home Depot, your local garden center, or even the closest supermarket during the spring or summer, and you’ll find 25-lb. bags of compost made from a variety of materials stacked up and ready to go. And the stuff sells like hotcakes. Such wholesale compost users as municipalities, major corporations, and other large landowners have also discovered that compost and mulch are effective, economical, and green alternatives to fertilizers.

Morbark, one of the major manufacturers of grinding equipment, got into the game in the late 1980s at the request of a customer looking for a way to solve a problem created by a new set of environmental regulations that prevented it from doing what it had always done in the past. "Morbark got involved in the recycling side of things in 1989," recalls Dan Brandon, marketing manager for Morbark. "Somebody came to us and said, ‘When we clear this 40-acre site for development, we have these huge stumps, and we can’t figure out what to do with them. And the state won’t let us burn them anymore.’" With the exception of W.H.O., Morbark’s story about how it got into the business of building grinders is similar to stories you’ll find throughout the industry–large-equipment manufacturers who built machinery for the forestry industry responded to market trends created by stricter environmental regulations.

"Because of our experience in the forest products industry, we knew how to build a machine that was heavy enough and strong enough to do that job and not self-destruct," explains Brandon. "That’s how we got into it. Now, without question, we sell more tub grinders than anyone in the marketplace. And of course they’ve gotten better every year. The tub grinder we make today is twice as good as the one we made five years ago, probably. We constantly work on them; we listen to our customers and dealers, and we make improvements all the time." There’s money to be made mining the abundant veins of greenwaste and yardwaste. But unless you’re in the business of making wine, distilling Scotch, or aging blue cheese, the time it takes to bring your product to market is a critical component to your monthly income statement. It isn’t rocket science to figure out that it takes a whole tree a lot longer to degrade than the same tree chopped up into half-inch bits.

Whether Descartes heard it or not, when a tree falls in the forest, Mother Nature uses all the tools at her disposal to break down the tree into little tiny pieces. The only difference between a commercial compost operation and Mother Nature is that the forest isn’t too concerned with creditors or employees who have mortgages to pay. A very important bottom-line consideration for any compost operation is that the smaller the carbon source, the quicker the compost goes to market. And that’s where the grinders and chippers come into play. Whether they are leased, bought (new or used), or contracted for, these monster Cuisinarts once designed for breaking up hay have become the backbone of every compost operation.

"Our customers kind of led us into this recycling thing because of this whole-tree chipping byproduct, which is bark and limbs, which was used as hogged fuel and one thing or another, but it really should be ground first," says Dave Benton of Peterson Pacific. "If you’re removing these parts from the tree, they are in pretty big pieces. And some of our customers started to ask about grinding this material, so we kind of fell into it through the back door. The major change that I’ve seen as the industry matures is that the equipment is maturing also. In the early days of recycling, people were using whatever machinery was available and modifying it to do the job. And that’s where tub grinders came in; they were originally used for grinding hay. But because they existed and people knew of them, they were adapted and enlarged to handle wood products."

"Over the years, everybody’s wanted to do bigger and bigger stuff and process more things, and so that’s why you had to build the machines bigger and heavier and stronger with more horsepower," notes Jeff Heilman of W.H.O. "Bigger material and more production are basically where our improvements have been. [The machines] have been beefed up, with more strength in them that can handle higher productions of bigger materials."

"You have customers who take the approach that they have to have the capacity to grind the biggest thing they’ve ever seen," says Benton. "Other people take the approach that they would rather have two smaller machines running side by side, which I think makes a lot of sense because you have built-in redundancy. If your machine goes down, you’re at 50% capacity. If you have one big [grinder] and it goes down, you’re dead in the water. But we build big machines and small machines, and we’ll sell either one of them. And there are people who definitely need the durability of the larger machines because they run heavy material regularly. It’s not necessarily size, it’s just that the wear factor increases as you go to a larger machine because they are built with thicker steel, tougher components, and bigger engines. We’ve got people running chunks of solid wood, and they need that capacity and that horsepower."

"All these machines have a big engine on them," comments Brandon. "They all have a hammermill or a drum of some kind that spins around and does the job. It’s what you put on the business end of things that makes the difference. They all have frameworks, they all have electronics and hydraulics; they’re fairly similar in many regards. It’s where the rubber meets the road, so to speak, that you’re going to see the greatest improvements, because people who are investing the kind of money they are investing in this stuff need a certain level of production and quality of product coming out. And they need the machine to run every day. You can’t have these machines down for a day or two–that costs these guys thousands of dollars. But regardless of how powerful or reliable these machines become, manufacturers have to keep the end user clearly in sight to ensure profitability [for the manufacturer as well as their customers] to capture a lion’s share of this growing market."

"As a company, we build our machines to keep them commonsense, keep them simple. Don’t put a lot of frills and whistles and bells on them, just make them grind," stresses Heilman. "I mean, we’ve got grinders out there with 15,000 hours on them that are still operating. But as important as the end user is, the most important considerations are the end products and the market conditions and marketing strategy to get those products in the hands of interested buyers."

"If you don’t have markets for what you’re producing, you’re buying very expensive equipment and tying up a lot of money and grinding and screening and so on," says Brandon. "And if you don’t have a place to sell that stuff at the end, in most cases, you’re not going to be successful. As this whole industry has matured over the last 10 years or so, we’ve seen that the successful operations are the ones who have focused on the marketing side. And they are developing decorative landscape mulch, compost, and even fuel in some parts of the country. They charge up-front to process the material, tipping fees, and then they charge again on the other end after they process the material. Those are the guys who are making money."

"The smart operators have figured out how to make money every time they turn around, basically. And they are solving a huge waste issue. I don’t have the numbers in front of me of how many millions of tons of this stuff are getting recycled every year, but that number is growing. And every year it gets larger. It’s all about production," points out Bob Strahm, marketing manager for DuraTech. "If you’ve got a few stumps to do, don’t go through the trouble [of breaking them up], throw them in there. But if all you’re going to do is stumps, chew ’em up first and break ’em down. You’ll get more life out of your tub grinder and more life out of your hammer. There are tools out there, like stump sheers, to do that."

Innovations Abound

Clutchless drives, winches, autofeed loading tracks, loaders, conveyors, and a variety of hammermill configurations and designs are all part of building the best possible machine for a particular application. And as the industry as a whole becomes more aware of how to use the machinery to maximize profits, expect new products and processes to show up that give businesses a real strategic advantage. If there is any doubt in your mind about how market-driven the grinder/chipper industry is, ask yourself if horizontal feed grinders would even be in existence if the majority of the material being ground was still hay. If a handful of hay gets thrown out of a tub and hits a nearby bovine in the head, the chances of a major lawsuit are slim to none. Replace that Mr. Bull or Mrs. Cow with one of your bipedal neighbors, and replace the handful of hay with a rock the size of a golf ball, and there isn’t a personal-injury lawyer in the country who wouldn’t take the case.

The same goes for chippers. If the principal users of chippers were tree services, then you wouldn’t find whole-tree chippers with loader and winch options. Now take that same market-driven source of innovation and run it forward to see what’s coming down the pike. Take, for example, California’s energy-deregulation debacle complete with rolling blackouts. In the late 1980s, there were approximately 70 cogeneration plants in the state. Today there are only 16. Obviously the rapidly rising price of natural gas in the state has created a business opportunity for cogeneration fuel producers. And as more cogeneration steam plants go back on-line to meet the growing demand for energy in the West, the supplier of fuel who can deliver the most efficient source will no doubt win a lion’s share of the market. Will that result in innovations to grinders or chippers? It might. If there is a way to create the ideal fuel size by modifying the machine that produces the fuel, then the savvy entrepreneur who comes up with that new twist should reap a healthy profit.

"Every year or two, someone pops up with a new idea. Manufacturing abhors a vacuum, so we all try to find a way to fill it," observes Benton. "What we’ve seen is a maturation process for the industry as people become aware of new end uses for products. But we’ve also seen that same maturation process for equipment. Virtually everybody in the business now is designing machines for a particular end use. And that’s probably the biggest reason we’ve seen the development of a horizontal-feed type of grinder…. As we identify new markets and new uses, the natural trend is to figure out how can I do that better than I’m doing it right now. Because what we’re really doing is taking existing machines that were developed for one purpose and continuing the process.

"The key to this business is profitability of the end products. If you can find a way to make that end product profitable, that’s where the growth is going to go. That’s where it’s going right now. I just keep hearing about people in the forestry industry bemoaning the fact that the past sources of readily available fuel for cogeneration plants are diverted into things that pay more, such as land cover and animal bedding and various composts–the value-added products. That’s going to be the prime mover in this industry–the economy.

"We do see some customers buy and upgrade to the larger end," continues Benton, "but more often than not that’s because they bought on the smaller end because that’s what they could afford. Once they prove their business plan and know that their model is going to make them some money, and they can afford it, they move up because they want more capacity…. In terms of volume, we definitely sell more machines at the smaller end, but that’s also a lower price point, and that could easily be the reason…. We basically have three size categories of machines that we sell, and we sell more of the smaller machines [2400-model series] than we do of everything else combined–or close to it, anyway."

"The government says you can’t put it in the landfills anymore, and you can’t burn it, so why not make a profit from it?" asks Leslie Kinnee of Bandit Industries Inc. "The biggest driving force right now is trying to take products that they can’t landfill anymore and can’t burn. By processing these materials and breaking them down, they develop new products that make money. Boiler fuel is coming back in style these days. We’ve even got customers grinding Astroturf to divert it from landfills."

"Once we make a sale, it’s almost like we’re in partnership with this customer," says Brandon. "We have to be able to support them. We have to be able to get them parts and service. We have to be able to answer their questions. Sometimes we even work with them on their business plan. How are you going to market this material? How much is it worth? What size material do you want to make? It really is a partnership. The successful manufacturers are the ones that can do all those things for their customers…. There are literally millions of tons of this stuff produced every year. You’ll see more and more people taking the opportunity to both solve an environmental challenge and profit from it. Our job is to help them with the right equipment to do that."

Author Mark Saunders is a newspaper and magazine journalist based in Denver, CO.