What to use as mulch?

A friend of mine is struggling to find a material to use as mulch in her vegetable beds.  Ideally it would be inexpensive, easily available and beneficial for the garden.  What came to my mind and what I have used in the past is either the shredded-up residue from utility line clearing or old unsold rolls of hay that farmers occasionally sell cheaply around here for "mulch" purposes.  That seemed good enough except for the fact that my friend is insistent that there be no possible residue of any herbicides or pesticides in the mulch.   Because it would be impossible and ridiculously expensive to test these materials it pretty much seems to rule these materials out for her.  My initial reaction to her fear of  contamination was to say that any possible residue would be so small and inconsequential as to be of no concern..,  but then she reminded me of a local case where people were buying composted manure that was essentially killing their garden plants...
a quote from an article concerning the matter...,     "employees at the dairy farm sprayed an herbicide known as GrazonNext HL over a hay field. The herbicide contained a chemical called aminopyralid, which is used for weed control, but is particularly harmful to tomatoes, beans, potatoes and other vegetables.   Cows at the farm later ate the hay. The cows’ manure — still carrying the chemicals then composted the manure and sold it unpackaged to customers."
    So perhaps her fear is justified and there really is nothing cheap and easily available  and beneficial for the "organic" farmer to use as a mulch.   Personally I still think that old hay or shredded trees is the best answer but I am wondering what others think and use,....


   

Wood chips. Huge quantities of woodchips.

My experience suggest that they are best used by letting them sit for a year first, ideally inoculated with mushroom mycelium first. See the various threads about wine cap mushrooms.

I also use my chips in the chicken coop as deep litter. The chickens physically break the chips down to fine textured mulch and add nitrogen.

Be careful with wood chips if you have dogs. I know mine has actually had some serious incidents due to chewing them and the wood getting stuck vertical in his mouth! Thank goodness I was around when he did it. Scary to see. I had to reach my hand in his mouth to pull it out while he was freaking out and thrashing around.

Also found this article on mulching mistakes: https://ngturf.com/top-six-mulch-mistakes/

Totally thought "volcano" mulching around trees was a good thing.... ekk.

oh....as I kept reading on this blog....what about using leaves? Using Fall Leaves for Mulch

Free, a lot of people would willingly give you access to them....depending on where you live.

If they are available, fallen autumn leaves make a fine mulch.  Ideally they should be shredded up so as to not mat and not easily blow away.  For years I raked my neighbors lawn so I could keep the leaves.  We both won.

Eric

May I ask what you used to shred them? Special equipment or just bagged them with a lawn mower?

Yes, aminopyralid herbicides in hay and straw and manure from animals that might have eaten hay or straw is a serious risk. Google how to do the "bean test" on it -- basically I think you just plant some beans into some soil with the suspect material, and watch it grow for a while to make sure that the bean plants don't grow deformed. But google it for more details.

Wood chips and autumn leaves would be safer, as herbicides aren't usually used on trees, and definitely not the aminopyralid class of herbicides.