McKinley Arborists

Tree Services

For almost 20 years, McKinley Arborists have helped cities, developers and home owners care for and protect their trees and property with expert advice and tree care. We understand that you have a lot at stake, and we take what we do very seriously. You can depend on us to provide careful inspection, diagnosis and reporting. Some of our tree services include: Arborist Reports, Tree Assessment and Appraisal, Hazardous Tree Assessment, Hillside and Environmental Consulting, Tree and Landscape Consulting, Tree Preservation Experts – Construction & Development, Tree Preservation Ordinance Writing Experts, Design Board, Planning Commission and City Council Meetings

Expert Arborist Testimony

William McKinley has over 28 years of experience in managing parks and general government facility landscape maintenance. He has over 20 years of experience working in municipal tree protection and code enforcement. McKinley Arborists has an outstanding reputation in the legal community for providing accurate and outstanding expert arborist testimony. McKinley Arborists provides clients with comprehensive litigation, consulting, and expert witness testimony on tree and landscape related cases. We will assist you through all phases of a dispute, from before the initial legal filing through discovery and trial. At McKinley Arborists we support the demands of litigation with comprehensive arboriculture analysis while addressing key issues with a clear and concise expert arborist testimony.


If you are looking to beautify your home, there’s nothing like investing in Arboriculture. McKinley Arborists can help advise you on what types of plants would thrive in your area. Having landscaping issues? Our arborists will play detective and help you figure out why your plants aren’t thriving. Protecting your existing trees takes more than installing protective fencing or adding mulch near a drip zone. Proper tree preservation begins at the planning stage. McKinley Arborists can provide valuable input regarding grade changes, strategies for working around your tree’s root zone, and recommend plant life that has the best chance of survival.

The Tree Doctor

William McKinley is known to many as the “tree guy” because of his love for trees and arboriculture. His vast knowledge and arborist certifications make him one of the best tree doctors around. His tree services include identifying tree diseases (tree diagnosis), and providing the cure (tree healing measures). If a tree or plant is not safely transported from one area to another damage to the roots of the plant can occur.  It is important to know about a tree sapling or plant seed before putting it into the ground.  Poor installation can lead to poor plant emergence or poor plant growth. Learn more about tree care from the Tree Doctor. Contact McKinley Arborists today to learn more.

Very good report. Thank you for making our decision a little easier to come to terms with.

James Carlson

, City of Sierra Madre

Wow what a wonderful comprehensive evaluation and report. Thank you so much for spending all of that time on it! I hope that you weren’t too tired! I appreciate your kindness and professionalism! I shall definitely write a wonderful review on yelp and or anywhere else that you think is important.


We were in the middle of construction on our new home and found that we needed to replace trees on our property. McKinley & Associates created a detailed tree report which we were able to submit to the city and get approved.

Maureen Ultimo

Tree Care: Soft Scale Insects

Oh no it’s the invasion of the soft scale insects! What are soft scale insects? There are many species of insects that are referred to as “soft scale” including: kermes scale, cottony maple, fletcher, and calico, and they mean bad news for your home. Soft scale eggs start hatching in mid to late June.  They
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Tree Services: Tree Care Tips

Tree Care Tips for the New Tree Owner Tree care begins from the moment you decide to purchase a sapling.  Before deciding which type of tree to purchase gather as much information about your environment as you can.  Study the soil, find out if the location gets lots or little sunlight.  Trees are similar to
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Arborist Tips: The Importance of Hiring an Arborist

You move into a new house, and naturally you start to beautify it.  Some people hire decorators to beautify the inside of their home, paying hundreds to thousands of dollars to impress with art pieces and unique furniture.  However, if life has taught me anything it’s that many people judge a book by it’s cover.
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Tree Services: Summer Tree Care Nightmares

We enjoyed a beautiful spring this year, and hope you did as well!  As we head into the hot, humid, and sticky summer months we here at McKinley Arborists know how tricky it can be to protect your plant-life against the perils of summer.  Keep an eye out for these summer tree care nightmares, and call McKinley Arborists for help. Top Three
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Do You Need An Arborist?

The first step in determining whether or not you need an arborist is to understand what an arborist does.  If you don’t know what an arborist is you are not alone.  The study of arboriculture isn’t as popular as many other professions, but the knowledge an arborist possesses is very important to homeowners.  An arborist
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Tree Care: What Does Your Tree Mean to You?

While for many people pets are like family, there are some of us who value our trees as much as we would a family pet.  Trees can beautify our homes, provide us with shade and clean oxygen, and add value to property, but just like animals trees get sick.  If you have pets you are
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Harsh Winter: 6 Ways to Protect Your Newly Planted Trees

The country is facing one of the harshest winters in history.  With temperatures in the negatives, news media are warning people to cover up.  We can cover up in sweaters, and protect are skin against frostbite, but what about our poor plants and trees?  At least 20 deaths have been attributed to the recent cold
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Winter Tree Care: Plant Ice Resistant Trees

If you are planning on planting trees this winter or this year, take time to consider the type of tree you will plant.  Not all trees are created equal.  Some can handle the heat, while others can take a beating from a winter storm and survive.  Consider your climate in order to make the best
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Tree Safety: Downed Power Lines

It’s raining hard in California, and while we desperately need the water, harsh storms often damage property and cause a variety of issues for home owners. High winds and torrential downpours cause mudslides and topple trees. Downed power lines often occur when cables get stuck in thick tree branches as trees fall over from moist
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Tree Safety – 8 Children Injured from Tree Crashing Down

Tree care is vital to our safety. Neglect to take care of your tree and the consequences could be severe. A large pine tree fell outside a summer day camp in Los Angeles county yesterday injuring eight children, two of them critically. The 70-foot-tall pine tree was 75 years old and fell without warning at about 5
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Give the Gift of a Tree

Tis the season for gift giving, and whether your just starting or wrapping up your Christmas shopping McKinley & Associates wants you to consider giving a tree. Why is tree-giving a good idea? They’re Inexpensive Unlike pets, trees are relatively easy and inexpensive to take care of. The average cost of taking care of a
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Tree Health: Insecticide News

Part of my job as an arboristis to be up to date on insecticide innovations and techniques. New products consistently enter the marketplace, and it’s my job to research a wide range of both products and techniques to find the best solution for treating each type of tree pest. While many tree care providers prefer to stick with what they’ve been
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Top 5 Reasons We’re the Right Arborists for You

Why McKinley & Associates is the right arborist service for you. As a business owner, part of your daily routine is explaining to potential clients why they should choose you over your competitors. This can be a daunting and expansive task if you’re in a competitive industry like arboriculture. Luckily, word of mouth has been great for
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