My first choice for an arborist if you love your old mature trees. Have a 47 year old Honey Locust shading a deck. Some branches are dead. Prefer having tree shaded deck instead of patio cover. Love extra light inside during the winter and shade in the summer. Mark and his team of three, chain saw wielders, Jakob, Kris, and Kyle completed trim and clean up, filled truck to top in time for trip to the dump less than 2 hours. Fast and efficient. Excellent choice of arborist, if you're interested in large tree preservation. Source for EnviroTree a type of natural external tree fertilizer and tree vaccination immunization (insects, fungus, tree diseases), liquid either spray or paint on bottom 3 feet of the tree trunk. read more

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Terrible customer service. From the lady on the phone who was rude and hung up to the owner who decided to call and say he wasn't coming to bid my job last min because it wasn't worth his time with my budget which he had no idea of what it was. Would never use this company! read more

We had a large Siberian Elm that was coming apart after the heavy snows. Mark called me back same day, came out that weekend for an estimate, and then took out the tree a week later. They arrived at 7:45 and were gone by 10:50. They were quick, efficient, and clean. No damage to our property and everyone was very nice. 10/10 would recommend and use again! read more

Tree cutting is ranked among the most dangerous jobs for a reason. They earn every penny of what you pay them. So I think your decision boils down to the type of company you want to hire for your project. Marks team postponed my job a few days until all weather conditions were favorable. A decision as simple as valuing the safety of your team over taking chances. That means a lot to me, because I had a personal friend of the family (who was a professional tree cutter in Maine fully harnessed) knocked out of a tree by an overhead limb snapping in a freak gust of wind. So I comprehend how technically challenging and dangerous the work can be, even if your taking safety precautions. The real difference you'll notice right way about this company vs others in Colorado is the commitment to doing it right. You have an owner who shows up to the site and has at least 40 years of experience and credentials behind him. A guy who actively helps his climbers see things they can't while in the tree. And I got to believe that is why they've won awards within the industry for a while now. I hired Mark's team to remove a large ash tree pinned between two homes. They communicated with each other about every cut, lowered the heavy wood down with pulleys, and did a beautiful job cleaning up. Easy choice for me to hire them in the future. The price was even similar to other companies I asked for estimates. I'll contrast that to my experience with another tree company here in Colorado. The day of the cut the contracted guys showed up asking me to supply them with canola oil to lubricate their chain saws. Their chains were dull and kept sticking. They dropped wood randomly with guys below not even paying attention. They cursed back and forth at each other, because nobody had brought a $7 wedge to control the cut. The whole thing felt like a miracle that someone wasn't hurt from shear recklessness. I've seen companies take short cuts with safety in-order to low ball their competitors. It's scary to watch thousands of pounds of wood just crash to the ground without much thought about it. And, no owner in sight. Best of luck with your choice. I feel really lucky to have found Marks team for my job. read more

I can not recommend Mortensen Tree Service enough. Mark removed a gigantic tree in my backyard 3 or 4 years ago. He had to have a huge crane reach over my home in order to gain access to it. It truly was an amazing operation expertly done. This last snow storm on May 19/20 almost destroyed a very large elm tree in my front yard. Mark came out the very next day after I called him and then had his crew out the day after that. They did another amazing job. Mark is the very best, efficient, friendly, dependable and reasonably priced. read more

Mark was friendly, fast, and easy to work with, so I don't understand the bad reviews. I needed to remove a dying maple tree and wanted to get a certified arborist. Working with Mark was a good experience from beginning to end. I will recommend him to friends and family. Some things I appreciated specifically were: Prompt service - got an estimate on a Saturday and work scheduled for the next Monday, three days later. He arrived on time for both appointments. Fair price - His price was lower than other estimates from competitors. Job well done - the tree was pretty close to our house and it fell clear. The stump was cut low, 3-4 inches, and rounded off for a low profile. They cut the trunk sections into firewood rounds for me. They cleaned up the yard of all sticks and debris. The entire job was done in about an hour, which was great for my busy schedule that day. read more

We were having some problems with our trees when we first called, Mark. They had totally over grown the area and were pushing up against the windows screens. I was very concerned about trimming the tree so that it was clear of the window screen, but I didn't want it to loose it's nice full look. After the service, the trees are beautiful. They still have that full look, but they are now completely clear of the windows. They're not lopsided at all. Shortly after that, we had a number of Aspens, between 20 and 30 feet tall, that have died and needed to be cut down. A few of these trees overhung an awning and I was concerned about damage. They brought down the trees with no problems, and helped give us some ideas as to what we can do with the now vacant location. They even helped answer a few other questions we had about trees on our property. We definitely recommend Mortensen and will continue to use them for any future needs. read more

Mark's been a force for good in our neighborhood for some time. In the Blizzard of 2003 and its aftermath, Mark was out there working to save the trees that could be saved, with his trained arborist's eye, and cutting down the ones that couldn't before they could fall on someone. Since he helped us then, he's been keeping our trees healthy and well-mannered. This year we lost two more trees that had to come down. Mark and his team kept the noise and disturbance to a minimum, and, which is very important, cleaned up beautifully afterward, rake clean or better, and made sure I was pleased with the job. Mark's prices are reasonable, and he gets back to you quickly when you want to consult him about what to do. He's earned those five stars over a long and valued relationship. read more

Mark and his crew did a great job. We needed several trees removed, and one tree trimmed. I will definitely be using Mortensen tree service again in the future. read more

I would definitely recommend Mark. He was very responsive and came out to quote on a weekend, which was awesome. He was prompt, did a great job, cleaned up the area afterwards and reasonably priced. I'd use his company again. read more

5/19/15 Today I spoke to Mort himself and was very disappointed in the way he handled the phone call. I've never used Mortensen Tree Service before, but was needing to have someone come and look at a tree in my backyard that needs help. Not only did Mort not know what he was talking about, he said to me "well I'll pass." Pass on what...the business! Wow so unprofessional and rude. I would never use Mortensen Tree Service, nor recommend them to anyone. If he's in the business of helping trees, but he'll pass. That says a lot about him and his lack of passion for trees. What a jerk!! read more

Excellent efficient service. Very pleased with the work. Mark is a competent well trained arborist. Have previously tried to do this ourselves and the end product shows. Better to have someone well trained do this. Very grateful and satisfied. Definitely will use again and can't recommend him enough! read more

Mark does an amazing job! When he came out to give an estimate for our three 35 year old pine trees and our 14 year old crabapple tree he took the time to present us with his wide knowledge base, extensive experience, and long history of excellent customer service. Mark's approach to tree care left out trees looking beautifully natural, functional and safe! He prices his service at a very affordable rate, leaves the job site clean, and get the job done right the first time! If you are looking for a master arborist to care for your trees at an incredible value then Mark and Mortensen Tree Service is the company for you! read more

I've been using Mark for the last three years. This guy knows his stuff when it comes to trees. His EnviroTree product has done wonders throughout my landscape. Trees that didn't offer much hope are now thriving! Even with the tough Fall and Spring freeze/thaws of the last two years my trees have stood the test compared to my neighbors. Unlike some of his competitors, Mark doesn't mess around with gimmicks or services that aren't really needed. He's honest and will tell it like it is. I would recommend Mark and his EnviroTree product to anyone. read more

What a mistake! We were hoping that by hiring an arborist we would be working with someone familiar with taking down trees safely and making good recommendations on how to care for what's left. We hired Mark's company to do the tree removals prior to landscapers coming in to finish our yard. Mark told us exactly what we wanted to hear unfortunately and failed to deliver. He bumped our project once after a storm so he could get more money from other side jobs and I should have taken the hint then and fired him. He did remove the 3 tree's we requested and only hit our house twice with the branches. He does not do stump removals as a matter of policy which we knew, but he also told us that landscapers were used to this and would finish the job since he would leave them so close to the ground. HAH! MAJOR issue with the landscapers, not to mention "close to the ground" turned out to be 15" off of the ground for one of them (Hardly close!). Our project costs are skyrocketing now due to hiring Mortenson. I tried to have a civil conversation with Mark about this and how we might be able to turn this into something that would leave both of us happy, he just lost his temper instead. Since the way he cut the stumps, our landscaping design was no longer possible without additional time, money and design changes, I asked him "how do we still get what we want?" He laughed, snatched the check from my hand and said "You don't. What you wanted was stupid anyway" got in his truck and drove away. Do yourself a favor, this guy doesn't want your business... hire someone else. We deeply regret hiring Mortenson. read more