Currently stumps that need to be cleared after felling trees are usually milled or excavated. While large tillers offer fast progress and are comfortable to operate, they often cannot reach the site at all. Smaller tillers, on the other hand, often have problems milling larger or harder rootstocks and offer only a shallow milling depth and slow progress. What all tillers have in common is that they can throw stones around, are very noisy, generate a lot of dust in dry soil and require a lot of energy.
Excavators do not have these problems and excavator-guided grubbers can grub efficiently even in the lower weight classes, but they often leave a lot of damage in the garden, are expensive and still cannot reach many stumps in the first place.