Read that table starting from the objective, not from the machine. The question is never which stump machine is best — it is what the site has to look like when the work is finished, and how many stumps there are per hectare.
These are different businesses with different economics, and the same rate card cannot serve both.
On scattered urban work, mobilisation and setup dominate. A machine that fits through a standard gate and sets up in ten minutes out-earns a more powerful machine that cannot reach the stump. Quotes should carry a mobilisation line, and per-stump rates should assume a minimum number of stumps per site.
On whole-area conversion — plantation, orchard or vineyard removal — stumps per hour drives everything, and grinding is usually the wrong technology entirely. A stump shear that extracts the root mass, or a forestry tiller that processes it in place, will beat grinding on both cost and site outcome.
The recurring failure in this category is a quote given without the information that determines the cost. Four things should be settled before a number is offered, and none of them can be established from a photograph.
First, the finish depth and what follows on that ground. Turf, paving and planting each need the stump removed to a different depth, and a machine that cannot reach it in one pass turns one job into two visits. Second, where the arisings go — grinding produces a mix of chip and soil that is cheap to level and expensive to cart, and a client expecting clean fill is expecting a separate operation. Third, whether the objective is a level surface or that the stump does not come back, because species that reshoot from roots need a different depth and method. Fourth, the location of underground services, established through the appropriate enquiry process and confirmed on the ground.
Where any of those cannot be settled in advance, quote with the assumption stated and a variation mechanism that triggers on a measurable condition — rather than a lump sum that carries the risk silently.
The same cost drivers read differently from the other side of the transaction. Three of them decide whether a stump machine earns.
Access governs more than capability. In urban and semi-rural work the machine that reaches the stump completes the job, and a larger cutter excluded from half your client base earns less per year than a smaller one that fits. Size against the access your work actually has, then check that grinding rate is adequate.
Tooth cost varies with the site rather than the machine, which is why it should be tracked per stump rather than per hour. Buried rubble, gravel and soil consume teeth far faster than clean wood, and a step change in the figure is the earliest signal available of either ground conditions or operator technique.
And the own-versus-subcontract decision turns on frequency of use, not on how often stumps exist. Own a grinder when stump work follows enough of your removals that subcontracting adds a scheduling dependency and a margin you are giving away; subcontract when it is occasional.
A specialised removal business, not conventional logging — and never quote it by visible diameter.
Does not grind the stump — it penetrates, splits, loosens, extracts and handles it.
Works below the soil surface — and should not be confused with an agricultural rotary hoe.