I've been angrily challenged by farmers.
I make the statement that tractors became dependable in the 1930s. In my area of Vermont I see the beginning of dependable farm tractors as The letter series Farmall by IH, (the dealer was local). Concurrent was the Ford 9N, & several other manufacturers we never saw.
Dairy farms began in the 1930s. Before that, farms were diversified. Dairy farms were all we had from 1938 to 1985.
After the Whole Herd Buyout, most VT dairy farms gave up.
My grandfather was a farmer. He did NOT make a living on milk. He averaged 25 lactating cows at a time. Electricity came 4 years before he died. He cooled milk in a concrete tank with water running through it, or with ice floating in it. Early, there was a creamery in town. When the creamery closed, milk was shipped by rail.
My grandfather never owned a tractor, but did have a "doodlebug" a homemade tractor from auto & truck parts.
He died in 1942.
To this day, I have never seen a crawler tractor involved in tillage. Wealthy farmers had them to build & maintain roads. Harry & Hugh Bromley had adjoining farms, each used a crawler in spring to gather maple sap.
I have never seen a crawler pull a plow.