George Cornwall real called the first use of a steam donkey was in Aug. 1881 on Salmon creek by John Dalbeer & Carson. Donald J. McIntosh was the 1st engr on that donkey. The first tractor was used around 1915 in Mendocino county by the Mend Lumber company. Ed Boyle, logging supt. used a 3 wheel tractor built at Maryville in in Mendocino county in 1915. Use of tractors grow slowly until about 1934. Then it want up rapidly. The 1st bull donkey was invented by David Evans in Humboldt County in 1891, mgr of Excelestor RW company. It was used near Freshwater, drawing strings of lags over skid road. The bull donkey is much larger than a steam donkey. The 1st one was a stationer plant. Later ones were mounted on sled runners.