Most people, myself included, dont charge on an hourly rate for this type of work. Because of customers.
IF someone said "I charge $50/hr"......usually the first question asked by the customer is "how long do you think it will take". Which is a tough question to answer. But lets say you take a guess and say "probably about 10 hours". Well.....you for **** sure better not go over $500, because the customer already has that in their mind. If it takes you 11 hours.....they will complain about that extra $50 every time.
Also, if hourly work is done, they will watch you like a hawk. Monitor how long it takes you to stop and get fuel, a drink, a sandwich, etc.
Also cannot really charge by the acre either. Every acre is different. Lots of stuff to mow around or not? Bumpy or smooth? How many acres? location? etc etc.
So that said, most that I know, including myself just charge a flat rate. I will ask important details like how many acres? (then confirm online using
Welcome to FindLotSize.com) I will ask when the last time its been mowed. (gives me an idea how fast or slow I will be going). I will look at the total acres. And look at how long its gonna take me to get to and from.
My setup with a 51HP tractor and 8' bushhog......I shoot for $75/hr. Tthough I never let the customer know this as they think $75/hr is just ridiculous as their "day" job only pats them $18/hr. (yes I have hear that before) So after all the info is compiled, I have a pretty good idea +/-10% usually, how long its gonna take me, including my drive time to and from. I take that guess, multiply by $75, and round it to the nearest $25 provided its above my $175 minimum charge.
IE: job is an hour away, and its 6 acres that was just done 3 months ago, and nothing to mow around. Pretty easy going and counting unloading/loading when there....I am figuring 2 hrs. Add that to the 2 hours round trip Im at 4 hours. 4 x $75 is $300. And if Im into the job for 4.5 hours, or 3.5 hours, it dont matter. Flat rate of $300.
But to answer your question.....I'll say it depends. Is this guy running an old ford, with trans driven PTO, and having to mow around alot of stuff? (slow going but cheap equipment overhead). Or is he running a modern tractor with HST and properly sized cutter that will be pretty efficient? (faster but higher overhead). Guys running old cheap equipment are typically slower and cheaper, working for beer money. But someone with more modern equimpent may charge more per hour (if thats how they choose to charge), but in the end charging $50/hr with modern equip may be cheaper in the long run than someone with old equipment charging $30/hr. And operator experience also comes into play.
I'd say that a modern tractor with 33HP, 5' cutter, and a good operator should be worth $50/hr at a minimum from the time he pulls out of his drive, till the time he returns to his house. And under average conditions, I'd say he should be able to do 2 acres per hour.