70 acres.. and trying to use a rotatory cutter ((lamen term = bush hog, bush hog = trade name)).
there are many tools of the trade, beyond just a rotatory cutter. that farmers use for crops, that may result in a lower HP requirement "within reason"
http://www.tractorhouse.com/ and look at "hay / forage equipment" plenty of listings of various 3pt hitch stuff. granted most of the stuff may not work well in "woods" and more geared for open fields but...
you don't need to "harvest" the weeds for say round bails or square bails, but simple get in there and just cut it down. it may look a bit ugly but "shrugs" cutting down tall woods normally leaves some ugliness. from large clumps of grass to windrows (rows of clumped cut grass), to some sharper pointed ends of tall weeds that were cut and everything a bit un-even.
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i do not have direct experience with the larger bat wings.. most tractors i see running around here. normally have each wing, 2 or 3 wings, and each one has a separate hydraulic lift on it. so they can deal with mowing out water ways, deal with fence lines, and other things. and lift and adjust wings as needed.
some bat wings i kinda look at and say.. huh? there are a lot of ditches along roadways to dirt roads going back into properties, along with water ways in fields, that can develop a pretty deep wash out in them. one little mistake in up keep to, just very ugly sudden quick rain falls that are in sense kinda like a flush flood going through some areas. and when i look at the wheels for these bat wings, both travel / road wheels, to then gauge wheels. and then look at the skids on some of the decks. i just kinda scratch my head. and wonder what were these folks thinking. it was like they designed the decks for a finish mower, instead of designing the decks for robust wash outs / ditches that can appear suddenly and show there ugliness, and getting the decks and blades caught up within the washouts.
there is also some issue if wings can withstand being unfold only partially, (a couple feet lifted up, or lowered even more. to deal with say stream banks, or lake/pond banks. and cutting over the edge some.
how are all the "slip clutches" are they easy to get to and adjust? or shear bolts?
are the gauge wheels / skid shoes, placed so when you do run over some bigger tree branches, the branches do not get lodged up into something. it has been a while i want to say "trip wheel design setup" 1 gauge wheel hits something, and the other guage coming up kinda flips over it, causing the one hitting the log or rut. to then also flip over the obstacle.
can you easily pull a wing completely off. and still use rest of the machine?
are there some turn single, break, night light on unit (other words rear trailer light setup). so you can run the wings down the road at night? so you can finish stuff up?
is there a place to mount a triangle slow moving sign on the machine?
can you shut down one wing completely. and keep the center and/or other wing turning? so you are not having a deadly blade spinning that has a wing completely folded up?
does the bat wing rotatory cutter, come with any sort of chains, or guards already installed. can guards be replaced or adjusted. to perhaps reduce some windrow effects. or guards be adjusted down some, to create some better suction power to pull stuff up into the blades (within reason)
does each wing and center if going with a 3 deck unit. have some sort of underneath deck ring. that goes around the perimeter of each blade? more about creating suction power. to lift things up and cut it ((this requires more HP to do so, err more suction = more HP))
is there any place on bottom sides of deck. were say a short few inches in diameter tree limb could get its end jammed up under the deck. and cause the deck to kinda lift up. as the deck was pulled across it? other words if not above question. is the underside deck pretty much a single sheet of metal. with little or no framing at all on bottom side. ((less HP required)) but may not cut as neat as in leaving a line of weeds that were never cut. ((assumption tires on tractor ran over the weeds, and these weeds never had a chance to get sucked up into the blades to be cut))
to note it. some folks actually use "rotatory cutters" aka lamen term bush hogs as finishing mowers. to cut there regular lawn with. and there is a market for different blade sets for just that for a bit better cut as well.
while other folks, just want to get the stinking weeds cut down, and don't really care about look. but rather just trying to keep things maintained, and keep thorn bushes, and thorn trees and other annoying little sapling trees at bay and/or clean up livestock / horse pastures.
