Moldboard Plow Basics

The moldboard plow cuts a slice of soil and turns it over, burying residue and leaving a clean surface. It is old technology that still earns its place on some farms, as long as you know its limits.

Key points

A moldboard plow cuts, lifts and inverts the soil to bury residue and sod.
Level the plow both ways and check first-furrow width before the real pass.
Keep points and shares sharp and replace them with correct parts.
Plowing exposes soil to erosion, so check local guidance on sloped ground.
Choose another tool if you want to keep residue or only need to loosen compaction.

How does a moldboard plow work?

Each bottom has a point that enters the soil, a share that cuts the slice, a curved moldboard that lifts and rolls it, and a landside that rides against the furrow wall to keep the plow steady. A coulter or jointer ahead of the bottom cuts residue so it folds under rather than dragging.

The result is a furrow turned upside down. Sod, cornstalks or cover crop get buried, and fresh soil faces up. That is why plowing suits heavy residue and sod breaking so well.

What tractor and hitch do you need?

Plowing is steady, heavy draft work. Many plows are mounted on the three-point hitch, while larger ones are pulled or semi-mounted. Check the plow's manual and your tractor's manual for the number of bottoms your model can handle and which hitch category applies.

Traction matters more than horsepower talk. Correct ballast, proper tire setup and working in a gear that holds steady speed keep the plow from lugging the engine down. Wear your seat belt under ROPS, and never ride or let anyone stand near the hitch during hookup.

How do you set up a moldboard plow?

Set up on level ground with the plow lowered on blocks or a firm surface. The goal is a plow that runs straight behind the tractor without constantly pulling to one side, cutting an even depth and width on every bottom.

Level the plow side to side with the lift link or leveling crank.
Level it front to back so the first bottom does not dig deeper than the last.
Adjust the width of the first furrow so it matches the others.
Check coulter position so it cuts just ahead of the point.
Make a short test pass, stop, and look at the furrow before plowing the whole field.

What are the advantages and drawbacks?

Plowing buries weed seed and residue, warms heavy soils in spring and can help break up sod for a new garden or pasture renovation. On a 5-acre homestead where you want a clean start, a plow can do exactly that.

The drawbacks are real, though. Turning the soil leaves it bare and exposed to wind and water erosion, uses a lot of fuel and time, and can form a plow pan, a dense layer under the working depth, if you plow at the same depth year after year. Check with your extension office before plowing sloped or erodible land.

What wear parts should you inspect?

Points and shares take the beating. Dull or worn ones raise draft, run shallow and make the plow suck up the tractor's power. Inspect them before each season and replace them with parts that match the manufacturer's specification for your plow.

Look also at bolts, shear or trip mechanisms, coulter bearings and wheel or depth-gauge pivots. Grease according to the manual. Welding structural parts is a job for a qualified welder, because a failed beam under load can injure someone.

When is another tool a better fit?

If you farm no-till or keep residue for erosion control, a plow works against your plan. A chisel plow or disk may give you enough loosening with less disturbance. For pure compaction problems, a subsoiler goes deeper without flipping the surface.

Think about what the soil needs, then pick the tool. Plowing is a good answer to some questions, not to all of them.

What does a pre-season checklist look like?

Before plowing season, inspect the whole plow with the tractor off and the implement blocked. Grease every fitting listed in the manual, tighten loose hardware and replace worn points and shares so you are not working on them in the field.

Then walk your ground. Remove rocks, old fence wire and stumps that could bend a bottom or break a beam. Mark any buried line locations, and call 811 before digging or working deep near utilities. A few minutes of preparation prevents most of the breakdowns plow owners complain about.

Grease and inspect all pivots, bearings and wheels.
Check shear or trip protection and replace with correct parts.
Inspect hitch pins, safety chains or lock pins.
Confirm lights and slow-moving vehicle emblem if you will travel on roads.

When to get help: For tractor ballast, hitch rating or plow matching questions, call your dealer service department. Any structural weld on a plow beam should go to a qualified welder.

Sources and further reading

Organization homepages are linked so you can search them for current guidance on this topic.

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