Beasts, Mulch and Dan
With over 30-years of service with the City of Toledo’s Division of Parks, Recreation and Forestry in Ohio, Dan Ledyard knows a thing or two about trees, mulch and machines. A forester by training, Dan is Forestry Supervisor and in charge of the City’s wood recycling and mulch programme, which he has been involved with since the very start.
With a population of around 300 000, the City of Toledo in northwest Ohio borders the state of Michigan. The City has an extensive metroparks system comprising of 12 parks with a combined area of around 40 km2. These along with street trees and other urban green spaces are maintained by the City via its Division of Parks, Recreation and Forestry, which employs around 30 staff in total.
– When I started working for the city in the late 80’s, we were still taking the material from our tree-care and park services to landfill. At the same time we had this site with our offices, tree-care fleet depot along with a plant nursery, said Dan.
– Subsequent changes in legislation regarding landfilling wood waste meant we had to start looking at other options for dealing with it. Recycling it into mulch, a product that we could use in our parks and Toledo citizens in their gardens, seemed like a good idea, Dan explained adding that the three components to produce mulch, the raw material, time and space, were there. In the early 90’s, Toledo began diverting its wood waste from landfill to the woodlot instead. Using a whole-tree chipper from the existing equipment fleet in the Parks, Recreation and Forestry Division, the material was chipped. However, in order to make the end-product, a contractor with a tub-grinder had to be brought in.
– We got into the business slowly, learning by doing as we went along to develop the product and the market, he told.
The arrangement worked well starting off, capitalising on existing equipment and having limited external costs. The business picked up, and in 1995 or thereabouts, the city decided to go full hog and invest in its own horizontal grinder.
The Beast to grind EAB-kill
City officials worked with Bandit Industries, located just a few hours away in mid-Michigan, and settled on The Beast Model 3680 horizontal grinder to produce mulch. It turned out to be a fortunate decision, too, as in 2002, EAB struck and has spread ever since.
EAB, the Emerald Ash Borer (Agrilus planipennis Fairmaire) is an invasive beetle native to Asia. It has wrecked havoc on ash trees (Fraxinus sp.) killing them by the millions in urban, rural and woodland settings.
– Ash trees are common in urban landscapes and residential areas across the US, said Dan.
In less than two decades EAB infestations have been confirmed in at least 22 states and two Canadian provinces.
– In 2002 when EAB was first found, it was close to here outside Detroit, Michigan. The devastation it has caused in gardens, parks, boulevards and woodlands would break your heart, said Dan, adding that the most likely culprit was wood packaging on imported goods.
It also meant that a massive effort was put into containment and clean-up works with increasing volumes of quarantined material that needed somewhere to go other than landfill.
– We managed pretty well since we already had the infrastructure up and running with the wood recycling and mulch operations, he said. In 2006, they upgraded to the current machine, the larger Model 4680XP, the Beast with a 45” capacity to handle the largest wood.
– This model is better suited to our operations as it handles larger diametre logs and brush piles that we were getting in as a result of the EAB fallout. Furthermore, it has a more powerful engine which means we could increase throughput and production, said Dan.
Mulch and mulch
Given that mulch is still being produced at the woodlot today it would appear that the move has proved to be an economically viable option too.
– We started off with one mulch product and today we have three different ones that we use ourselves and sell to anyone who wants to buy it, here at the woodlot or delivered to within about a 30-mile radius, he said.
The delivery service has proved very popular as most clients are private residential properties who buy season after season. The dark almost compost-like landscape mulch is made using brush and lop ‘n’ top material that comes in from private gardens, landscapers and other tree-care operators bring into the yard.
– We grind this material in the Beast with an open gate to bypass the screen. This gives us a mixture of fine and coarse material that we just pile and let settle. We turn the pile once, and then after at least six months regrind it with a closed gate, explained Dan. The chip mulch is similar but has a different texture and made from chips the tree-care and landscaping crews bring in from their daily operations. This material needs only grinding after the initial curing.
The speciality product is the playground mulch made by grinding logs in the Beast to the final size in one pass. Unlike other mulch producers, no colour is added to any of the mulch.
– Our playground mulch is a popular product both for public playgrounds and private ones at schools and kinder-gardens, he said.
According to Dan, it is lab tested to meet federal standards for impact absorption but unlike other materials used in playgrounds, it doesn’t get too hot during the summer so children don’t burn themselves on it.
Biomass to energy options?
After getting a handle on the operations, seeing the type of and volume of feedstock readily available, the disposition of the site itself and equipment, the obvious question is what about biomass for energy purposes?
– I’m glad you bring it up and I have to admit that it’s a challenge trying to figure out a way forward on that score. We need to keep in mind that as a municipality owned operation, we have to be careful about what we do so we’re not infringing on the private sector, said Ledyard with a hint of frustration.
It’s not from a lack of trying different ideas. Firewood comes to mind prompted by the sight of one of the largest log-splitters that I’d ever seen not mention large diametre logs in the yard.
– I know what you might be thinking but the log splitter was actually bought in to break the largest butts for the grinder, he said pointing out a number of gigantic butts.
– We get enquiries for firewood around about this time of year as folks tidy up their backyards preparing for the winter. There are quite a lot of residential wood boilers and houses with fireplaces so we tried it as a seasonal thing, said Dan.
It wasn’t run it as an outright business, selling cut and split seasoned firewood. Instead, the public was allowed to come and more or less help themselves to cut cordwood from a designated area.
– But we had to put a stop to it because of insurance and liability issues, he explained
– We supplied a furniture manufacturer with woodchips to complement their fuel intake but they’re located a bit far out of from here to make it economically feasible. Some years ago we supplied woodchips to a local steelworks, but they only used it over a couple of months to tide them over, Dan said.
What about the city itself – it is already using mulch in its parks and playgrounds, why not extend the programme to include biomass heating in public buildings and schools? According to Dan, the main stumbling blocks are the low cost of natural gas and the relatively high investment cost to make a switch from gas to a woodchip boiler contra replace the gas boiler with a new one.
– We’re trying to convince them to take a more holistic view and thinking of proposing a project here at our facilities. We’ve our own buildings to heat, maybe we get ourselves into a small combined heat and power unit, he mused.
A tracked future
Maybe a third-party could be persuaded to set up a larger heat and or power project on site.
– We’ve loads of space on the site directly adjacent to the New York – Chicago railroad, we have the power infrastructure, the biomass fuel resources that could be expanded to include that of private landscape and tree-care operators. You see the possibilities are numerous, Dan remarked.
He is right, there is plenty of opportunities. Perhaps the recently announced grant by the USDA to ”expand wood products- and energy markets” may just be the ticket for Dan Ledyard and others like him to get biomass heat and power rolling in Toledo and elsewhere.
For the near future though one thing is high on Dan’s wish-list, a new horizontal grinder. Not that anything is wrong with the current one, it does what it is supposed to do, is well maintained and looked after.
– It’s now in its tenth year of service here, so it is time to start thinking about trading it in for a newer one. The only major change I’d like compared to now is having it on tracks instead, ended Dan Ledyard.
This article was first published in Bioenergy International no. 6-2016. Note that as a magazine subscriber you get access to the e-magazine and articles like this before the print edition reaches your desk!