No species line was published for this address, so what it will and will not take is a question for the mill itself. The species guides are the other half of that conversation: what you are holding, and what it is normally worth.
It is the only facility the Montana sources list in Deer Lodge County, which is worth knowing before you plan a haul: the next gate is in another county. The Deer Lodge County section of the state page shows it standing alone, and all 99 Montana listings cover 26 counties.
Anybody searching for a sawmill near me needs more than one gate. If this one will not take your wood, the nearest other listings are Philipsburg Public Schools in Philipsburg, 20 miles away, Treasure State Correctional Enterprises in Deer lodge, 21 miles away and Deer Lodge Central Park Center/Elementary in Deer Lodge, 21 miles away. Distances are straight lines between the coordinates the sources published - not road miles, and not a statement that anybody is buying.
None of this says whether the gate is open or what the load would fetch - no agency document records that. A price comes out of a sale run properly: the landowner's guide to selling timber takes the steps in the order they happen, and sealed bidding puts one tract in front of several buyers at once instead of taking the first number offered.