In my opinion no firewood is not a chattel, but a fuel souce like propane. Meaning that the firewood on a property is not listed in the Included or Excluded chattel list, and what normally happens here in Muskoka is that once the deal is firm and close to closing the seller will ask the buyer if he would like to buy the remaining firewood, the price is normally set at the present replacement value.
Definition of a chattel
n. an item of personal property which is movable, as distinguished from real property (land and improvements).
Unlike propane, where the lawyers get involved and the seller has the propane tank filled on the day of closing and the purchaser pays for a full tank of propane, irrespective of how much was filled on the day, the lawyers normally do not get involved with firewood, as there is no easy measure of what full is when it comes to firewood.
Also the agents in the deal also normally do not mention the firewood at the time of the offer, as the seller could use some of the firewood between time of signing and closing, so it is just simpler and better for all parties, for the seller and the buyer to negotiate directly or via the respective agents just prior to closing as to the sale of the firewood.