I too would like to know which it is; Southern Yellow Pine, Pine (general sense), Framing lumber, Whitewood, Air dried, and Kiln dried have all been mentioned here.
I would be more than happy to help maintain the machines and if once a month doesn’t seem like enough than it should be bi-monthly. Waiting till someone has a problem to address a machine is waiting too long in my opinion. In the shop I used to work in we did weekly cleaning/grease/wax and then once a month was deep clean and blade changes. This was a place where the blades were cutting 40-50 hours a week on various woods.
Is there any interest in a general cleaning class of the machines? Simply hitting it with compressed air and checking there is no build up or waxing the slides and cleaning the paper. If more people knew to do these things before/after cutting it would cut down on wear and tear.