Best way to get mulch a 1 acre site

Hey smart people,

I had someone ask me for a good way to put a thick (2 foot) mulch over a 1 acre site. He really wants to cover it well and thick. My current thought is to use round bales of hay/straw and find/rent a round bale mulching device. But then the question is how many round bales would be needed to cover the site in such a thick layer.

I know in the past I have seen some machines that would chew up a round bale and spit it out in a controlled manner, but I have never had to go searching for such a machine. And I really have no idea how much straw/hay it would take to thickly mulch an area.

Does anyone have any ideas?

I don't know the answer to that question, but I have seen video of a couple that covered 2 acres with woodchips about that deep. They used 512 dump truck loads if I recall correctly. I would think it would be cost prohibitive to do it unless you had some free source of material. That being said, perhaps the person doesn't care what it costs. I'll be curious to hear the answer though.

Commenting to see if anyone has any good answers. I've been trying to mulch my garden, which is less than a 1/4 acre and I'm having a hard time getting enough mulch to suppress the weeds. I'm trying to go the free/extremely cheap route though so it might be a bit easier if he's willing to pay a bit of money.

Some sources of mulch to look into;
Cardboard-To be used as base layer, may reduce the need for 2ft of mulch. This is the easiest thing to come across, lots of stores will gladly give you broken down boxes.
Spilled/spoiled hay-Lots of people would be happy to let you clean the hay out of their stalls or give you spoiled hay they can no longer use as feed. We got a lot of our mulch from our messy goats. Has the added benefit of fertilizer (manure) already mixed in.
Pine straw-We have literal tons of pinestraw around us for free. It's just a pain to collect
Woodchips-Lots of tree services will have woodchips they need to get rid of, some might even be willing to deliver. Many counties also have a recycling center with free/cheap woodchips. We have not been so lucky with finding a place like this.
Yard waste-Now is the time when people start cleaning up their yards and they produce a lot of waste. Might be able collect whatever is by the road or find out if there is a service that collects it (probably the county) and see what they do with it.

Hope this helps!

Grow it. Get a ton of poplar/cottonwood/willow stakes during early winter, stick them in the ground at roughly 1 meter spacing and give them a year to get established.

It might be prudent to grow some low-but-dense annual biomass crop under it during the following growing season.

Run over the whole place with a brush mower type machine the following winter. Repeat annually until you get the depth you want.

I would guestimate you'll get 6-9 inches per year depending on growing season/fertility factors and weather or not you grow that under-biomass-crop.

As an alternative, you might grow a perennial clover undercrop to supply nitrogen to the trees. That's probably the best option now that I think about it.