Use of non-composted woodchips
This winter I had a tree service remove a partially dead white oak. The tree was about 2+ feet in diameter at its base and around 150 years old. In grinding the stump out, the workers left a huge pile of very fine wood chips—almost like sawdust! They recommended leaving the wood chips in place to settle and fill the void. My question is whether I can use the unweathered wood chips as garden mulch this spring (seeing as the pile is about 18” high and 5 feet across.) Also, can I replant this area immediately? I am thinking of a large shrub such as elderberry.
Yes on using the wood chips as mulch.
No on planting in the raw wood chips/sawdust material. If you want to plant in that spot, dig out the backfilled sawdust and replace with soil and compost mix.