35' Poles were and are still the common height. I worked for an outside electrical contractor, and the majority of poles in our inventory were 35' poles with a smattering of 40', 45' and 50' poles for special uses. A 35' pole was placed in a 7' holes resulting in 28' above ground for mounting the crossarm.
By the way the majority of poles were shipped in gons as the 35-50 foot poles would easily fit in a 52'6" gon which is how we received them at our yard.
Another point, all the scenery gurus want you to roughen up the poles with a steel comb or whatever, poles were smooth so there was less chance for a lineman's hooks to pop out when climbing the pole.
