Tillage, Harvesting, and Forage Equipment
Tillage, Harvesting, and Forage Equipment tests your ability to set, adjust, and maintain the machines that work the soil and bring in the crop. Expect primary and secondary tillage tools and wear parts, combine headers, threshing and separation, cleaning-shoe adjustment, loss diagnosis, forage harvester cutterhead and shear bar setup, baler knotters and density control, and moisture targets.
Tillage fundamentals
- Primary tillage (moldboard plough, chisel, disc ripper) fractures and buries residue; secondary tillage (field cultivator, disc, harrow) prepares the seedbed and levels the surface.
- Residue management, depth control, and wear parts drive performance. Worn sweeps and shovels increase draft and leave untilled strips; check bearings and hubs for play and heat.
- Working soil at the wrong moisture smears sidewalls and creates compaction layers.
Combine settings and losses
- Crop flows from the header through the feederhouse to the rotor or cylinder and concave for threshing, then separation, then the cleaning shoe where chaffer, sieve, and fan clean grain before it enters the tank.
- Rotor or cylinder speed and concave clearance set threshing intensity. Fan speed and sieve openings set cleaning. Reel speed is usually slightly faster than ground speed.
- Losses occur at the header, from unthreshed heads, from separation, and out the back with chaff. Total loss should be near one percent of yield.
Forage and baling
- Forage harvesters rely on sharp knives and a correctly set shear bar; clearance and knife condition determine chop length and power draw.
- Round and square balers depend on correct knotter timing, density settings, and moisture. Small square bales are usually baled near 15 to 18 percent moisture; too wet causes spoilage, too dry causes leaf shatter.
- Shear bolts protect the machine; always replace with the specified grade and size, never a hardened bolt.
Worked example
A combine leaves unthreshed heads in the straw but the grain sample is clean with no cracked kernels. The reasoning points to insufficient threshing, not over-threshing. Increase rotor or cylinder speed slightly, or close the concave, then recheck losses and grain damage. If you instead opened the concave, unthreshed heads would increase further.
Traps that cost marks
- Raising fan speed to chase a dirty sample and blowing grain out the back.
- Setting threshing aggressively and cracking grain.
- Installing a standard bolt in place of a shear bolt.
- Baling above the safe moisture range and stacking spoiled bales.