Heck, yes, use that wonderful stuff! I would compost the sawdust (add nitrogen such as spent coffee grounds), & use the chips for mulch. Don't dig woody materials directly into the soil in your beds, as it can cause "nitrogen draft" (the loss of nitrogen that the plants need); if it's on the surface or if it's composted first, it's wonderful.

Wow, thanks for all the great feedback. My goals for mulching are 1) retain moisture and (mostly) 2) suppress weeds. We moved into some wooded acreage a few years ago, and hubby created a 20'x30' flower garden with beautiful black swamp dirt - loaded with weed seeds. Even though I've sprayed with herbicide (over a dozen times), used gallons of Preen and pulled weeds till my hands hurt, I can't keep ahead of those hardy weeds. Last year I put down a thick layer of wood chips, hoping to stop them. The weeds laughed, and I again have a bumper crop. Last weekend I spent two full days digging them out by hand, root & all. Hopefully that'll help? BTW, the "expert" was featured in the most recent issue of "This Old House". I just figured he knew more than I - which unfortunately for him, isn't saying much. :P

Here is some info from North Carolina State University on the subject that I think is particularly good. (Link below for full article.) "Aminopyralid, clopyralid, fluroxypry, picloram, and triclopyr are in a class of herbicides known as pyridine carboxylic acids. They are registered for application to pasture, grain crops, lawns, certain vegetables and fruits, and roadsides. They are used to control a wide variety of broadleaf weeds. If these herbicides are used on a pasture or hayfield, they apparently donâÂÂt harm the animals grazing on the pasture or eating the hay. But some of these herbicides can be persistent and may remain active in the hay, straw, grass clippings, and manure, even after they are composted. Some of these herbicides have a half life of 300 days or more and aminopyralid has been reported to remain active in compost for several years. A problem sometimes arises when these materials, particularly manure and compost, are applied to fields and gardens to raise certain vegetables and flowers. The herbicides of greatest concern are picloram, clopyralid, and aminopyralid. The garden plants that are most sensitive to this class of herbicides are tomatoes, potatoes, lettuce, spinach, carrots, peas, beans, dahlias, and some roses." "Some roses." Not sure what that means, it certainly would be good to know. Most of the product labeling for these types of herbicides says to wait 18 month before you plant sensitive crops where it has been used. I think porkpal is right that aminopyrolid is the longer acting one. For the others 18 months is not a long time for manure waste to sit around composting--and waiting for the chemical to go inactive. If I had access to lots of high quality compost that I though might be tainted I would seriously consider a small test garden with sensitive plants to experiment with the compost in. I think it could be well worth the effort. For those of us in the U.S. 2-4,D is still the predominate herbicide used for livestock hay production and it doesn't pose this problem. There are issues with this though and there is a small risk when using manures you don't know the background on. Fortunatly more people--farmers, livestock operators etc. are becoming aware of the issue. Here is a link that might be useful: Manure/herbicide Info

Terri: I have been getting horse manure since 2011. The pile is over 15 feet tall, in OPEN AIR, I have to climb a hill to get to the top of the pile, where it's most composted & black, dry & no odor. But the bottom of the pile is wetter, stinks, more salt accumulation, plus less decomposed. Aerobic decomposition (with air) is better than anaerobic (without air), so I would leave your pile OPEN. Sunlight will zap out mold, bacteria which cause odor. There's more fungus & disgusting molds WITHOUT air, and if those fungus get into one's lung, one can get Hypersensitivity pneumonitis. From Wikipedia: "Pulmonary function tests show reduced diffusion capacity of lungs for carbon monoxide (DLCO). Many patients have hypoxemia at rest, and all patients desaturate with exercise.[2] Extrinsic allergic alveolitis may eventually lead to Interstitial lung disease.[3] From WebMD " Hypersensitivity pneumonitis: Interstitial lung disease caused by ongoing inhalation of dust, mold, or other irritants." I got that one time from breathing in bagged peat-moss, and the medical bill was over $6,000 with bronchoscopy, and antibiotics for my pneumonia. Husband got fresh horse manure by mistake this past Oct., so I spread that out at the back of my garden. Just went outside to check today, Jan 30, and that pile has NOT DECOMPOSED WHATSOEVER, as if I got fresh horse manure yesterday !! The pile shrank, but I still see chunks of woodchips, and long & intact strands of hay. So it DID NOT DECOMPOSE whatsoever in 4 months of zone 5a winter. If I want it to be black like dirt at alkaline/neutral pH, it would take at least 1 year with warmer summer temp.