They live in the same category because both derive value from a long-lived planting plus the land under it, and they diverge on almost everything else.
On the small end of timber, buying a tract directly is genuinely possible at modest acreage. Rural southern pine land trades on a per acre basis that varies enormously by region, road access, and how old the standing timber is, so a small tract can be within reach where a comparable vineyard acre cannot. Vineyard ground in an established appellation carries a name premium on top of the vines, and the vines themselves cost real money to establish, so the per acre figures you saw aren't a typo.
The costs that don't appear in listings: property taxes, which many states reduce substantially if you enroll in a forest or agricultural use classification, though the rules and the penalty for pulling out early differ state by state and you have to apply. A written management plan from a consulting forester, which some of those tax classifications require. Periodic forester services, often billed hourly or as a percentage of harvest revenue when they run a timber sale for you. Boundary maintenance and liability insurance, especially if you lease hunting rights. Reforestation after a final harvest, which is a real cash outlay years before any return.
If you don't want to own dirt, the listed timber REITs and some funds hold the same asset class in a form you can buy in small amounts, and you give up the harvest-timing control that makes direct ownership interesting. That tradeoff is the actual decision, more than the acreage.
