A stump killer is a herbicide that stops a freshly cut stump from sprouting, but the dead stump stays where it is, while stump grinding takes the stump itself down below the ground in one visit. Granular stump remover is a third thing: it only speeds up rotting, which still takes weeks to months and ends with digging or burning.
Three products, two jobs
The shelf in the garden center mixes up two very different things. A stump killer is a herbicide. One common bottle, Bonide's Stump Out Stump and Vine Killer, lists triclopyr as its active ingredient and says it kills stumps and prevents sprouting. A stump remover is something else. Spectracide's granules, for example, list potassium nitrate, which is there to help the wood break down. Iowa State University Extension adds that some remover products also carry a herbicide such as triclopyr. So turn the package over and read the active ingredient before you buy. It tells you which job the product does, and neither one makes a stump disappear.
What a stump killer actually does
A stump killer stops a live stump from pushing up new shoots. It works by soaking into the living wood just under the bark and riding the sap down into the roots. That only happens on a fresh cut. NC State Extension says water-based herbicides should go on as quickly as possible after cutting, oil-based ones within a two-hour window, and that on larger stumps the outer inch of the cut face is the part to cover. Iowa State is blunt about the limits. Herbicide poured onto a stump long after the tree came down does not help it rot. It runs off into the soil. The stump you are left with is a dead stump, standing exactly where it was.
What a stump remover does
Stump remover is a rotting aid. The Spectracide label tells you to drill several one-inch holes up to twelve inches deep, pour granules in each, fill them with hot water, and keep adding water for several days. It then says to allow four to six weeks, and that breaking the wood down may take weeks or months depending on size. At the end, the label says, the porous stump may be removed or burned. So you still dig, chop or burn it out. Iowa State says these products tend to be simply a form of fertilizer, often potassium or sodium nitrate, and that the rotting itself can take years on a big stump.
What stump grinding does
A grinder does not wait for anything. Its cutting wheel works across the stump in passes and turns it into chips until the whole thing, root flare included, is four to eight inches below the ground around it, or lower still when sod or a new bed will cover it. Once the machine is in position an ordinary stump goes quickly; reaching it is what takes the time. You are left with a mound of grindings, a shallow hollow under it and the main roots still in the soil, where they rot out of sight. See stump grinding for how a visit goes from arrival to clean-up.
Side by side: time, mess and what is left
Put the three next to each other and the trade-offs are plain. A stump killer takes a few minutes on the day the tree is cut. It costs little effort, but the stump stays, solid, for years. A stump remover takes some drilling, a few weeks of watering and waiting, and then a dig or a fire, and on a big hardwood that wait stretches out. Grinding takes one visit and leaves the yard ready for soil and seed that week. Grinding also ends sprouting from the stump in nearly every case, because the buds at the base are turned to chips. The real question is whether you need the stump gone or only need it to stop growing.
Safety: the label, the soil and the trees next door
Treat both products as chemicals. The Spectracide label warns that potassium nitrate may intensify fire, calls it an oxidizer, and says to keep it away from heat and flammable materials and out of reach of children and pets. Iowa State advises staying away from products that contain picloram, sold as Tordon, near a home landscape. University of Arizona Extension adds a point most people never hear. Neighboring trees of one species can be linked by grafted roots, so a product brushed on one stump may end up in the tree beside it. Shoots that come from a kept tree's roots should never be treated. Follow every label exactly.
Which one fits your stump
Use a stump killer when a tree is being cut today, the stump can stay, and you only want it to stop sprouting: a fence row, a woodland edge, a thicket of invasive trees. Use a remover, or plain rotting, when there is no deadline and the stump is out of the way. Grind it when the stump is in the lawn, by the drive, where the mower goes, or anywhere you want to use the ground this year. A killer on the day of cutting and a grind later are not in conflict either. If sprouts are the worry, read how to stop stump sprouts before choosing.
Common Questions
Does stump killer make a stump rot faster?
No. Stump killer is a herbicide that keeps a live stump from sprouting. Iowa State University Extension says herbicides are not beneficial for promoting decay, and that herbicide poured on a stump well after the tree came down mostly runs off into the soil. To speed rotting you need moisture, decay fungi and nitrogen, or a grinder.
Is stump remover the same thing as stump killer?
No, and the names cause a lot of wasted weekends. Stump remover granules are usually potassium nitrate, a fertilizer that helps the wood break down over weeks or months. Stump killer is a herbicide, such as triclopyr, that stops sprouting. Read the active ingredient on the label to know which one you are holding.
Can a stump that was treated with stump killer still be ground?
Yes. A treated stump grinds like any other once the product has done its work, and grinding below grade is the step that actually gets it out of the way. Mention what was used and when it went on when you ask for a quote, and keep the bottle so the label is to hand.
What to Do Next
If the stump has to go rather than just stop growing, send a photo of it with a tape across the cut face, plus your town. Call (828) 574-4474 and Jordan will tell you what grinding it would take. For the full list of things that set the number, see what stump grinding costs.