Stones surfacing every winter frost-heave cycle turn a paddock into a mower-wrecking, stock-injuring liability, and a stone burier is the implement that fixes it in one pass rather than a season of hand-picking.
- A stone burier flips and buries surface rock while levelling the seedbed in one pass β buy the 1.65m Sierra SSTB165 for anything over 30HP.
- Working widths run 1.25m to 1.65m and match Category 1 to Category 1N tractors from 15HP to 55HP.
- Depth control, not raw horsepower, decides whether rock actually gets buried or just shuffled sideways.
- Skip a stone burier under 1.45m if the paddock has rock bigger than a clenched fist β it will ride up and stall.
Why this matters
Rocky paddocks in New Zealand aren't a one-off problem β frost lift pushes new stone to the surface every winter, and hand-clearing the same 2-acre block year after year burns weekends you don't have. A stone burier uses reverse-rotation tines to lift rock, drop it below the working depth, and drag a fine tilth back over the top, all in one tractor pass.
The alternative β raking, picking, or running a rotary hoe that just chops rock into smaller rock β costs more time in 2026 than it did a decade ago, because contractor day rates have climbed and most lifestyle block owners are running one tractor solo. Getting the sizing and depth setting right the first time is what separates a paddock you fix once from one you fight every season.
What you'll need
- A Category 1 or Category 1N three-point linkage tractor, 15HP to 55HP depending on burier width
- A stone burier sized to your working width β 1.25m for sub-compact tractors, 1.45m-1.65m for anything 28HP and up
- PTO shaft rated to your tractor's PTO speed (check 540 vs 1000 rpm before you buy)
- Ballast or loader ballast if your tractor is light on the front axle β burying stone loads the rear linkage hard
- Safety glasses and hearing protection β flying stone is a real risk on first pass over a rough block
- 2-4 hours per acre depending on stone density and how many passes the paddock needs
The steps
1. Walk the paddock and grade the stone problem
Drive or walk the block first and note where stone concentrates β usually low spots, old cultivation lines, or anywhere fill was brought in. This tells you whether you need one pass or two, and whether a 1.25m or 1.65m burier makes sense for the area. Skipping this step is the single biggest reason people buy a burier too small for the job β a 1.25m Sierra SSTB125 on a 3-acre stony flat means three times the passes a 1.65m unit would need.
2. Match burier width to tractor HP, not the other way round
A 1.65m stone burier needs 30-55HP to run the reverse-rotation tines through dense or clay-heavy soil without bogging the PTO. Undersizing the tractor stalls the rotor mid-pass and leaves half-buried stone sitting proud, which is worse than leaving it alone. The Sierra SSTB145 at 1.45m suits most 28-45HP compact tractors and covers the bulk of lifestyle block paddocks in one or two passes.
3. Set working depth before you start the pass
Depth is set via the rear roller, and getting it wrong is the most common mistake on a first-time burial: too shallow and stone stays in the topsoil where the next frost pushes it straight back up; too deep and you're dragging subsoil clods into the seedbed. Aim for 60-80mm on most Sierra models as a starting depth, then adjust after the first 20m based on how much stone stays buried behind the roller.
4. Run the first pass slow, in first or second gear
Speed through a rocky paddock on the first pass burns tine wear fast and throws stone instead of burying it. Run at 3-4 km/h for the initial pass over unknown ground, then increase speed on repeat passes once you've confirmed the depth setting is holding. Watch the roller behind the machine β if stone is bouncing rather than rolling under, you're too shallow or moving too fast.
5. Cross-pass at 90 degrees on heavy stone areas
A single directional pass misses stone sitting parallel to your travel line. On sections flagged as heavy in step 1, run a second pass at right angles to the first. This doubles the tine contact on any given square metre and is standard practice for turf prep and new paddock establishment, not just a nice-to-have.
6. Follow with a rotary hoe or roller if seedbed finish matters
If you're prepping for pasture seed rather than just clearing rock, a follow-up pass with a rotary hoe fines the tilth the burier leaves behind. Some Sierra stone buriers ship with an integrated seeder option, which saves a pass entirely if pasture renovation is the end goal rather than just stone removal.
7. Check and grease tine bearings after the first 5 hours
New stone buriers need a bearing and bolt check after the first working session β rock impact loosens fasteners faster than normal soil work. Grease every 8-10 hours of use after that, and inspect tines for wear whenever you notice the burial depth drifting shallower than your setting.
Common mistake: running a burier at transport speed across a paddock you haven't walked first. Hitting a rock the size of a rugby ball at 8km/h can bend a tine or shear a shear-bolt, and it happens more often than owners expect on a first pass.
Troubleshooting
- Stone still visible after the pass β depth is set too shallow. Drop the roller setting 15-20mm and re-run the same line.
- Tractor bogging or PTO stalling mid-pass β burier is too wide for your HP, or you're running second gear on ground that needs first. Drop a gear before dropping the RPM.
- Tines throwing stone forward instead of burying it β travel speed is too high for the density of rock in that section; slow to walking pace until the roller is turning stone under, not over.
- Uneven finish, ridges left behind β rear roller isn't tracking level, usually a linkage height issue rather than the burier itself. Check top-link length before blaming the implement.
- Shear bolt failures on rocky ground β expected wear item on genuinely stony paddocks; carry spares and don't upgrade to a heavier bolt than specified, it just moves the failure point to the tine itself.
- Seedbed too rough for pasture seed after burial β run a rotary hoe or roller pass behind the burier rather than seeding straight into the burier's finish.
Tools and resources
- Sierra stone burier 1.65m β the widest single-pass option in the range for 30-55HP tractors
- Sierra box blade 7ft β useful for final grading on paddocks that need levelling as well as stone burial
- A Sierra rotary hoe for fining the seedbed after burial when pasture seed is going in
- A guide on inspecting a used tractor implement before buying if you're weighing a second-hand stone burier against new
What to do next
Once the paddock is buried and levelled, the next job is usually pasture renovation rather than more stone work β check the chain harrow guide for pasture renovation on lifestyle blocks for the pass that typically follows a stone burier when you're re-establishing grass cover.
FAQ
What does a stone burier actually do?
A stone burier uses reverse-rotation tines to lift surface stone, drop it below working depth, and drag soil back over the top in a single tractor pass. It's built for landscaping, turf prep, and paddock renovation on stony ground rather than general cultivation.
What size stone burier do I need for a 30HP tractor?
A 30HP tractor suits the Sierra SSTB145 at 1.45m working width, which is rated for 28-45HP Category 1 tractors. The 1.65m SSTB165 needs 30-55HP and Category 1N linkage, so check your tractor's PTO horsepower before stepping up in width.
How much does a stone burier cost in 2026?
Sierra stone buriers range from roughly NZ$3,995 for the 1.25m model to NZ$4,895 for the 1.65m version in 2026, with seeder-equipped models running NZ$6,995-$7,995.
Is a rotary hoe better than a stone burier for rocky ground?
A rotary hoe chops soil and shallow rock but doesn't bury larger stone below the seedbed, so it isn't a substitute on genuinely rocky paddocks. Most owners run a stone burier first, then follow with a rotary hoe to fine the tilth.
How deep should a stone burier run?
Most Sierra models start at 60-80mm working depth, adjusted after the first pass depending on how much stone stays buried behind the rear roller. Too shallow and frost heave brings the stone straight back up the following winter.
Can a stone burier double as a seedbed prep tool?
Yes β the Stone Burier with Seeder 1.65m combines stone burial with a seeder pass, useful for pasture renovation projects where you're clearing rock and reseeding in the same operation.
What HP tractor does a 1.25m stone burier need?
The 1.25m Sierra SSTB125 is built for Category 1 tractors from 25-45HP, making it the right size for sub-compact to small compact tractors rather than larger 4WD units.
Do stone buriers work on clay soil?
Stone buriers handle clay-heavy soil but need more HP to keep the rotor turning without stalling, and working depth may need reducing slightly on wet clay to avoid dragging large clods into the seedbed.
One last thing
The seeder-equipped 1.65m model at NZ$7,995 looks like the expensive option next to the NZ$4,895 standard SSTB165, but if pasture renovation is the actual goal rather than just stone clearing, it removes an entire tractor pass β on a multi-acre block that's real diesel and time saved every single season, not just this one.