I have read all the posts on stump grinding pricing. Basically there are three “camps”:
1. “Inchers” = charging by diameter inch
2. “Area” = charging by the area of the stump and occasionally taking into account height to charge by volume (have to remember high school math and pi x radius squared)
3. “Time” = charging a hourly rate
After using all 3 methods in different scenarios I have concluded there is no single method that works in all situations. “Inchers” inevitably charge less for bigger stumps. “Area” and “Volume” result in charging, arguably accurate but extremely high prices that are likely not market-competitive for large stumps. “Time” results in undercharging for very small stumps.
Now some of these methods can be modified to take into account the other methods benefits. For example, “inchers” can charge $2/inch for 30” to 50” and $3/inch for 50” to 70”. Doing this is simply a way of compensating for the fact that the area (the amount of work) increases by 4 times when the diameter doubles. That being said, anyone that charges a flat inch rate, that doesn’t change as the size of the stump increases, is doing themselves a huge disservice.
So after much thought, excel formulas, reading posts like this, talking with a veteran stump grinder with +30 years experience and my own lessons learned the hard way here are my recommendations and what I am doing. Feel free to knock holes in it and criticize. We all learn from the conversation (maybe even convince everyone to start charging more for those really big stumps).
1. Determine your minimum. This will be different for everyone depending on years in business, equipment used, location, financial situation, and your personality. The range I have seen on the postings is about $50 - $250. For me, its $60.
2. Determine the max size of a stump you will grind for your minimum. For me its 30”. That would take me about 10 – 15 minutes. It’s a personal choice but the decision can be guided by your choices in step #3 below.
3. Determine your per inch rate after the minimum. For me its $2/inch from 30” to 42”. Then $3/inch from 42” to 60”. I will make more per minute on the 43” stump vs. the 60” stump. I just accept this fact and appreciate that I can give a ballpark estimate over the phone, the customer can understand it and there are some efficiencies of lining up on one 60” stump and grinding away vs. doing four 30” stumps (both equal the same cubic inch volume).
4. Determine your hourly rate for big stumps. I consider a big stump anything bigger than 60”. I am not recommending telling your customer what your hourly rate is. But you should know your hourly rate. Then use your experience to determine how many minutes it will take to grind it. If I have a 90” ash it may take me 80 minutes. If I have a brand new Carlton 7500 and 30 years experience it may take only 30 – 45 minutes. For me my hourly rate is $150 (keep in mind this is only for big stump scenarios). That guy with the brand new carlton may be $300/hr. The tricky part here is that I would only be using this method on a 61” stump so my price is already $183. So its only at the 73 minute point that I would use this method. Remember to keep it simple, so call it one hour. To summarize if a job is going to take me longer than a hour I will charge $180 + $2.50/machine minutes for every minute after the initial 60 machine minutes. Man that sounds complicated. But if you try to keep it simple by charging by the inch you will undercharge big time. If you use area or volume you will be likely be charging way above the market because most operators don’t think about pricing this way. If you use the hourly rate you will be able to decide if this particular stump is worthwhile to you. You just have to be able to know ahead of time what your machine is capable of doing in that specific situation.
So to wrap up this very long post, let’s talk about variables. Variables to consider:
Type of tree: soft or hard. All my pricing is based on a medium hardwood like an Ash.
Tree condition: rotten?
Access: front yard grind and go or backyard tight gate pain in the rear
Roots
Depth required
Stump height: For stump height I treat all stumps 6.5 inches or less the same. I do this because my machine can grind that height down to a reasonable depth in one pass. Anything above that I will have to take two (or more) passes. To account for that I use an admittedly complicated method of determining the total cubic volume then comparing that to my pricing standards for the 6.5 inch height stump. For example a 12” stump height x 30” diameter is equal to a 6.5” stump height x 40” diameter. So I would charge anywhere from 1.5 to 2 times more for that higher 30" diameter stump because the cubic volume doubled. Note that the relationship between height and cubic volume is different than the relationship between diameter and cubic volume. With height the cubic volume doubles as the height doubles. With diameter the cubic volume quadruples as the diameter doubles.
Summary:
OK so sum all this up.
· $60 minimum up to 30” stump
· $2/inch for stumps 30” to 42”
· $3/inch for stumps 42” to 60”
· Use $150/hr rate for stumps that exceed a $180 charge using the per inch method.
· For my area, to stay competitive, I can keep it simple and continue to charge $3/inch for stumps greater than 60” to 100”. It’s my personal decision to get the jobs vs. taking the objective mathematical approach but not getting the job.
· After 100” its kind of a wild west situation and just have to know how much time its going to take and then decide what makes it worth it to you. There is an argument to be made to letting people take these huge stumps for a low bid and hopefully learn a lesson.
Some quick things about me to help evaluate: I’m a rookie. Been in the business for two seasons. Grinding is my side-business. Learned stump grinding two decades ago during college summer breaks. I use a very old Carlton 7500 and an equally old Carlton 4400-4. 420 stumps complete and counting. Average stump diameter 35".
