Hardwood timber in OK /AR? The vast majority of the harvestable timber in either one today is plantation planted pine. What little hardwood there is very slow growth stuff. (Think 100 years from seedling to harvest. ) All of the old growth hardwood was cut before WWII and what replaced it was either planted pine or scrubby hardwood regrowth. Even 50 miles further south, the hardwood regrowth to harvest is 35 years or so.
According to my McCurtain County relatives it's true that most of the hardwood within a 25-mile radius of Broken Bow or Idabel was harvested clean by the 1970's -- but they're still hauling wood in from north on the flanks of Blue Mountain up on US 259 -- not in the quantities seen 40-50 years ago, but still enough to make the operation profitable. But Weyerhaeuser, who bought out Dierks, the old regional lumber "kings", back in the '60's, has centralized their hardwood operation (again, concentrating on white oak, which is apparently their most profitable wood variety) with extensive plantation operations between Dierks (gee, I wonder where the town name came from!) and Murfreesboro, AR (they've owned or leased that land for about a century). Having dealt with oak suppliers in my own business (loudspeakers), I've been told that while it's true that there's a "waiting time" from planting to harvest -- actually calculated at about 28 years for California red oak and a bit more for the harder white variety -- Weyerhaeuser, being one of the "800-pound-gorillas" of the industry, has the resources and the available acreage to keep a rotating supply source, where successive plots are harvested and replanted on about a 2-3 year cycle, and for the next cycle moving on to another mature plot for harvest, repeating the process.
But it's unlikely much of that would even be considered for barge traffic -- the company, and Dierks before it, has their own railroad running from Valliant, OK, where it services their mill and also interchanges traffic with BNSF there, east through Broken Bow to De Queen, where product is switched to their long-time partner Kansas City Southern. The railroad -- the Texas, Oklahoma, and Eastern, is registered as a common carrier (it also serves the Tyson plant in Broken Bow), even though 80% of its carloads are Weyerhaeuser input or output. The line exends east to Dierks and then turns southeast to Hope, AR, where it services yet another mill and interchanges traffic with UP. But most of the raw lumber and finished wood product from the mills goes to De Queen and is transferred to KCS which moves it to KC or Shreveport for wider distribution (or even export via Port Arthur, TX). This arrangement has been in place for as long as Dierks and its successor have been harvesting lumber from the Ouachita Mountains; the chances that it'll change to barge for the marginal cost difference -- as well as the disruption of its existing distribution chain -- are vanishingly slim.