What materials should I use to make my Mushroom Food Plot™?
While every bag of Mushroom Food Plot™ spawn you order comes with detailed instructions, we get a lot of questions about whether or not specific materials will work to build food plots.
Mushrooms are ROT, so we need to feed it things it can eat. Great examples are hardwood sawdust and mulch, straw, chopped corn stalks and cobs, shredded leaves, bean hulls and chaff, pulp shreds, chipped cardboard etc, all of which are considered a waste resource. Out of all of these waste materials, hardwood mulch/sawdust and straw are the most readily available to folks. Not Pine, not Cedar, Cypress, Fir or Spruce, not Walnut and not Locust which is rot resistant, which is why we use it to build furniture and other items.
When it comes to wood chips, sawdust, mulch etc, softer hardwoods like Aspen, Basswood, Poplar, Box Elder, Maples etc produce mushrooms relatively quickly, however because they deteriorate faster they won't be as productive long term. In contrast, denser hardwoods like Hickory, Oak, Beech, and Hornbeam work well; they are slower to colonize and produce mushrooms up front but because they take longer to break down they also generally produce for a longer period of time.
For many people, finding a local source of these materials can be troublesome. I urge you to please try to get the materials from a local source wherever possible; small family farms and local businesses need your support. Tree trimmers, Municipalities, Landscape Nurseries and Sawmills will generally have an option for you.
However if it is not an option, here a few ideas. Tractor Supply, Rural King, Fleet Farm etc, whatever the name is, your local "farmers mall" should have bales of straw or bagged compressed straw. They should also have Aspen bedding used for critters in a compressed bale/bag, hardwood fuel pellets in bags and bagged hardwood mulch (not Cypress or Pine etc). Likewise, you can likely find these same products at a big box store like Walmart, Home depot, Lowes etc or order them off the web. These items will work well if you hydrate them, but because they're dried and compressed for storage, we must add water for our scenario which generally involves an overnight submersion.
Pictured below is a Mushroom food Plot constructed by Dr. Jim Brauker on his Coldwater MI property using straw and bagged hardwood mulch from his local hardware store. 
I personally utilize the free or dirt cheap resources around me as much as possible. I get a ton of wheat straw for free by sweeping the trailers for the farmer who hauls straw bales. In addition to loose straw, I often get broken bales and "bad bales" for free or at cost. After Halloween I cruise the streets looking for free bales of straw leftover from autumn decorations, similarly large outdoor events in the winter are likely to have free bales after the event is over, especially if it rains on the bales.
Here in the Upper Peninsula of Michigan or Da UP eh, sawmills dot the landscape and most of them have mountains of sawdust. The local spot for me is full of great guys who have seen me on TV on the 906 Outdoors show "Discovering" a pile of times when I taught them how to find edible foods at their land. So they usually load me up with sawdust with their front end loader in exchange for my eternal gratitude, patience and occasionally a few bags of mushrooms.
In the future I plan to invest in a 3 pt wood chipper implement for the pto on the tractor and hopefully score a manure spreader to modify for wood chip dispersal.
Of course, a dump trailer and a tractor with a bucket would be nice too.
For now though, my old truck is still hauling, I unload by hand and it's worth it to me as a poor boy to do so.