A good material for this is the local wheat straw I can buy for $2.00 a bale delivered.
The problem is that the straw is a bit l seedy and needs to be broken down a bit.
In the past I have used a lawnmower for this purpose but we don't have a working one at the moment. This isn't a problem because we don't have any lawn or grass to mow!
So how to break down the straw??
I have an area in the main chookrun that we have covered with shadecloth and fenced off.
I had attached micro-spray sprinklers around the top of this to allow the straw to be watered down if there was no rain (quite often). However with our water restrictions I'm back to waiting for the rain or organising myself to water on Saturdays!!
The bales are placed in this area and broken up roughly by me. Then the chooks come in and dig it over
They have a great time searching for any wheat seeds and after the area has been wet, they dig right down to ground level to get any bugs and worms living in the cool damp soil.
After about 2 weeks it is ready! I put the sprinklers on at night for a short while (or wait for rain) and a couple of days later rake and pick up the now broken down mulch into a wheelbarrow.
It is now moist and dust free allowing it to be used as mulch on my vegetable gardens.
Most of these areas are watered from beneath by drippers so every drop of water put on the plants stays right where it is needed and doesn't evaporate away.