Finish Mower vs. Rotary Cutter for Mowing Pastures?

I have 12+ acres to mow/maintain on my new farm. The pastures have been cut for hay for the last several years so there are no scrubby trees or bushy weeds, however there are some broad leaf weeds in the grass. I’m shopping for a 40HP tractor and something to mow with. I was looking at getting a rotary cutter/brush hog but I recently read some information about finish mowers and wondered if that would be a better option for me. I also read that while I could use a 6 ft brush hog, I could upgrade to a 7ft finish mower because they require less PTO HP to operate. An extra foot of cutting width will come in handy. What do you all use to mow pastures?

Both types cut grass. Finish mowers tend to be optimized for more lawn-type maintenance at lower heights (3-4") while rotary cutters/brush hogs are optimized for higher and rougher situations. (6"+) Some pastures would be fine being cut with a finish mower if they don’t have a lot of “stuff” and under 6" height is fine with you. Otherwise, the rotary/flail/hog type is the better choice. IMHO, of course.

Mr IF, mowing expert for the last 17 years, says get a robust finish mower. Your pasture sound like they are in good condition and you don’t need a bush hog. We have both but most use the finish mower and a zero turn. He says the finish mower was much better for knocking down weeds on hilly ground. You also can get the broad leaf plants treated by your local farmer’s coop. Our farm is 132 acres, so we have lots of practice.

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We use both, the bush hog & the Ferris zero turn. The zero turn is a foot shorter but faster and the bush hog is harder on hills. We have four pastures and they take about 4hrs for the 8acre field, 6hrs for the 11acre and about 3hrs for each of the 6acre fields. You can’t tell by the cut and they both do a nice job.

I use a 5’ finish mower I bought from Tractor Supply. I like it very much. Just as robust as the more expensive one I bought years ago, and used up, from John Deere.

My pastures are very clean, and the finish mower makes them so beautiful. You can adjust the height. I am not sure about the tallest cutting. Mine is adjusted to about 5" and it could go higher.

Riding on my outside grass jump field after it has just been mowed with the finish mower is like walking barefoot in new carpet! Heaven!

I use a finishing deck like this http://www.farm-king.com/Region-US/landscaping/finishing_mower/index.php behind a JD4310 for cutting along fence lines in most of my pastures as well as around the house. I then use a bush hog for the rest of the job. The design of the finishing deck allows me to work close to, and even under, fence lines meaning a LOT less weedeating. It also cuts quite close, meaning there’s less stuff to eat near the fence. If a horse is going to get in trouble it’s going to be along a fence line. Reducing the forage supply reduces the motivation to hang around the fence. So far it’s worked pretty well.

Finishing decks are much more expensive than basic bush hogs. I would think finishing mowers would be, also. You can buy the Farm King above for $1600, more or less, depending on where you buy it. A standard duty 6’ bush hog can be found in the $900-$1000 range. The finishing deck will require a bit more careful “care and feeding” as it has a belt drive system (vice a slip clutch or shear pin). I’ve been through two finishing decks but only one bush hog.

Each has its own advantages, but there is some overlap. I have both and use both when one or the other is required.

G.

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Although there is some overlap, I think the rotary cutter is better suited to the job. Even if there’s no brush in your field, a rotary cutter will handle taller/thicker grass much more easily because it’s not trying to mulch it as small as a finish mower. I also don’t like the idea of that small of mulch from a finish mower decomposing being available for horses to eat for the same reasons they shouldn’t eat lawn mower clippings. Finally, it would be more robust in case you did encounter the odd rock, stick, etc.

Not sure what tractor you’re looking at, but I have a 2011 John Deere 3520 that is 37HP with 30HP at the PTO. I wouldn’t run any larger than a 5 foot rotary cutter with my machine. Even with the 5 foot cutter, I still have to slow down a tad in really thick areas when the RPM’s start dropping - the problem will only be worse with a larger cutter. You’ll finish much faster maintaining 10-12 MPH than bogging down with a slightly larger cutter.

If you’re looking at a 40HP tractor, your PTO horsepower could be similar to mine. Take your PTO horsepower (not tractor horsepower), divide by 5 to find the max width implement it can handle, then go down one size so it can handle the worst you throw at it. I can’t tell you how mad I’d be having to deal with a 6 foot box blade, snow blower or cutter on my tractor. Deep/wet snow, a full box blade uphill and thick/tall grass are no problem with my 5 foot implements but would be with 6 footers.

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I question the lower horsepower requirement of a finish mower. The finish mower blades spin faster and have multiple spindles to drive. On the SAME grass, a bush hog has an advantage.

A friend uses a finish mower on his pastures. It is broken again. As usual… I think it fragile compared to my Hardee rotary cutter.

I use a finish mower all the time. But my pastures and ‘yard’ are a well maintained Pecan Grove. No real brush, just grass. I try to keep up so the height is always 4 - 8 inches, depending on the weather. With all this rain lately, I had to mow one pasture “with my tail in the air” just cutting the 2 foot tall grass to one foot tall. - the entire mower deck can be raised off the ground in infinite degrees. Then when it dries out again I’ll go back with the mower on a ‘normal’ 4-5 inch height. It does a good job mulching, and the horses dont care to eat the cut off grass. When it’s all done, it’s beautiful. I love my finish mower.

Yup. So far my bush hog has out lasted two finishing decks and is working on beating Number 3!

Still, I have one because for some tasks it just works better and the utility justifies the price.

G.

Fields are currently well-maintained, but there’s always the risk that the pastures may “get away” from you a bit–maybe due to travel, tractor’s in the shop, or whatever. I’d want to be confident that I can knock down a shaggy field if I ever needed to. That said, you can rent a brush cutter for isolated situations.

If you’re going to mow often enough to actually help improve the pasture, go with a finish mower. I actually use a zero-turn and mow the grass from 8-10" high down to 5" high on a regular basis to keep weeds down and encourage proper grass to grow.

If you’re going to come around 2x per year and shorten Jumanji, get the bush hog because you won’t have much grass.

Obviously I advocate the former approach. Land is too valuable and grass is important to soil retention, horse nutrition, and reducing pollutant runoff.

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I have a Woods 7 ft. finsh mower – love it. Cuts beautifully and the 7 ft. vs the 6 ft. I used to have, is a time saver! My New Holland tractor is only 26 HP. Just enough to operate a 7 ft. finish mower. Wish I could go bigger, but can’t.

I use my finish mower on my nice fields exclusively now. They are brush free, in nice shape from consIstant attention over the years. I really like the even cut, side chute spreads the trimmings well to prevent windrows that kill growth. 4 wheels make it ride evenly on all ground, for even cutting every place. My best growing grass is a wet spot, so I will go thru with mower slightly in the air to top grass off, then go thru a second time to get grass down to desired height. I don’t want grass cut shorter than 5 inches. That length protects soil, plant roots, provides lots of good grazing. I quit mowing if it gets very dry, leave things alone until we get good rain again. Mower wheels are really easy to adjust in height, a feature you want going from pasture to lawn mowing. Takes me 2 minutes literally, to change height on all 4 wheels. Most of the time is for wiping grease off my hands! Ha ha

I use a Ford 930B, came with the Kubota tractor. I take off the cover and blow off any cuttings in the belt area after I am done mowing fields. Also blow off the tractor radiator, any clippings that are on it. Dandelion seeds will make a mat on radiator, causing poor engine cooling, overheating. They have been an inch thick on the radiator sometimes, which was a real surprise the first time it happened!! Found them while trying to figure why engine was running hot. Tractor is cold-hearted, NEVER runs hot! Dry matter in under mower cover can overheat belt, moving pullies, causing excessive wear or a fire. Keep your machines clean, prevent problems.

I did use my brush hog in the beginning of pasture keeping, it handled the tough stuff coming up from fields not being used for years. I did not like the scalping it did on our rolling ground. Cutting could have inconsistent heights as we went along because tractor and brush hog were one unit. Tractor nose up had brush hog down tight to the dirt or tractor nose down lifted brush hog up high off the ground. I really only use the brush hog now to mow outside fences on the neighbors property. Ground is very rough, can have branches down, roots, holes in my path. Better to abuse the brush hog than the nice finish mower. I am the only one doing any trimming there, so ground and brush, trees, are always different each mowing session.

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I also use a finish mower for my front pasture; it’s really pretty, and it’s what you see when you drive up to my house. It wouldn’t handle it if the grass were tall though. I second the carpet like feeling - it’s awesome.

Darn, now I want a finish mower. :frowning:

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Reviving this thread as I am contemplating this decision as well.

Meant to add… have Hay field converting to pasture. No brush (we had three cuts off the field this year), but it’s not a lawn either… We have some lumpy ground. I’m leaning towards finish mower and lifting it high w three pt to keep from scalping the field. Following with a chain harrow drag to start to smooth out the lumps next season. Is that enough to protect the finish mower?

I run the disc over my fields to just cut the soil with lines. Not turning it back into dirt. I then drag the WEIGHTED chain harrow to smooth the ground of frost heaving, deep hoof prints, for smoothing things out. Might have to drag rougher places more than once. Disc cuts allow air in the soil, cut thick grass plants apart to spur better growth, prevent rainfall sheeting off the soil by catching and slowing water runoff. I do my dragging with chain harrow teeth down, using tires tied on top for my weights. Without weights above my chain teeth and harrow just hop around on top of soil doing no good at all. Fields do look a bit rough, grass is spotty in places, may have roots up, when done. Yet grass re-growth is fast with spring rain and an application of fertilizer. In a very short time field looks like a lawn of intense green and you are mowing weekly!

Pastures should be soil tested for application of correct needed minerals. Taking hay off, grazing, removes needed minerals from the soil and you need to put them back for a good crop of grass. Horse poop is not enough for your only fertilizer on the soil. I graze heavily, apply fertilizer needed with my soil test results. I try to fertilize yearly if weather doesn’t mess me up.

You need to do this field work as early as possible to have rain getting grass going well, rain-in your fertilizer down in the soil. Get Ammonium Sulphate instead of Urea in the mix, insist on it. Urea is a problem for horses and other livestock grazing, they can founder on it. Both cost the same when i asked about it.

Have to say riding over smoother ground while mowing is MUCH nicer than rough ground!

Horses here are locked off the fields as they get body used to grass diet again with very restricted turnout. Minutes only, by the timer! They not allowed on wet fields. Finally getting full turnout usually in late May. We take our time with the turnout so bodies can develop needed digestion stomach flora for grasses over a few weeks. No lamanitic issues happening here!

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I would go with this. Once the weeds get tall, they can be hard to cut.