You can use wood chips from just about any species, as they are a great soil amendment (once self-composted) and a good topdressing mulch in the meantime. If you prefer to let them sit aside (say, if you're not ready to use them once they're chipped), you can let them start aging and composting in a separate pile, though as with any mulch or compost material, it would be good to periodically turn it to maintain good aeration so it doesn't become anaerobic (a risk with deeper rather than shallow piles). We caution against the use of cardboard if you can avoid it. While more scientific study is needed (Washington State University has  done some work with this), some types of cardboard may contain "forever chemicals" (PFAs, etc.) from the manufacturing process that might leach into the soil below. Plus, a "sheet mulch" (something solid rather than loose like natural bark/wood chips) could hamper the soil's access to oxygen and moisture, which is not desirable for the health of beneficial soil microbe communities, soil insect life, and any live roots of desirable plants that might be in the area. A wood chip mulch should suffice by itself, and has been used successfully in that way (including at Patuxent Research Refuge) to smother a variety of plants (weeds, turfgrass) in an area where new plants are being installed. What few tough weeds may make it through that layer can be carefully spot-treated with herbicide or dug out by hand.

Miri