Since I in was born in Rolla and grew up here in the county (still living on the family farm), I am well acquainted with Fort Dette and Fort Wyman. You are correct about the wood found from Fort Dette. The fort was a Greek-cross design and was a single story with a usable roof, portholes on the lower area for muskets and the roof mounted the cannon. Main purpose was to overlook the railroad which ended in Rolla. The fort was not finished by the war's end and the locals quickly dismantled the fort for building materials. Fort Wyman, being a earthern fort, much like Fort Davidson, lasted into the early eighties when the fort land was sold and commercial buildings replaced what walls of the fort existed. I went to grade school at Colonel John B. Wyman elementary which is on the same hill of Fort Wyman. In the late 1960s, some teacher decided that we needed an ecology trail near the school (which I thought was odd since all the kids on my bus grew up in the woods...). While cleaning out the trail, a cannon ball was discovered. Not realizing it till I was much older, all the kids who attended that elementary entered and left the school under the watchful gaze of the Federal army (a large portrait of Col. Wyman who seems to stare at anyone who sees the portrait hung inside the front door of the school and probably hangs there still). Making sure the locals are still Reconstruction compliant I suppose...
The Salem fort was the unfinished Courthouse and was burned during Price’s Raid into Missouri. In October 1864, James A. Jamison and Simeon Richardson came into Salem and burned the courthouse and jail. The courthouse was being used as the headquarters of the Union army for the district. "Genuine Jim" Jamison had escaped from Gratiot prison in St. Louis the previous year. Jamison would run with Bushwhacker Bill Wilson and Anthony Wright of Phelps County during this time as well. By 1866, the Missouri governor Thomas C. Fletcher had a $250 reward offered on Jamison for bushwhacking and arson.