Ball Tread Tractor Co in Detroit built is first 12-12 YUBA Ball Tread tractor year 1912. Yuba Construction bought the company yr 1914 and continued building tractors in California till yr 1913.
Yuba Mfg. continued bulding its own 12-15 and 18-35 models and more between 1946 and 1951 as a possible successor to the "Ball Tread" crawler tractors manufactured by Yuba in the early teens.
So there are two different styles at YUBA, see slider.