By Drew Olson Special to OnMilwaukee.com Published Nov 12, 2008 at 3:25 PM

The publicity brochure for the Tree Care Industry (TCI) Expo describes Mark Chisholm as an acrobat, expert rope climber, tree physiologist, competitor and thrill-seeker.

Upon hearing that, we figured we had to talk to the man.

Chisholm, one of the world's foremost arborists, will be in Milwaukee this week for the TCI (formerly National Arborist Association) Expo at the Midwest Airlines Center. He recently won his 16th straight title at the New Jersey Arborist's Chapter of the ISA's Tree Climbing Competition, then finished among the top five at the International Championship in St. Louis.

We caught up with Chisholm in advance of his Milwaukee appearance.

OnMilwaukee.com: All kids like climbing trees, but I don't think many aspire to be the "fastest" or "best" tree climber in the world. How did it happen for you?

Mark Chisholm: I originally got started like many did in the industry, through family. More specifically, I wanted to go to work with my father and his co-workers, which included my older brother, Steve. I was impressed by how close they all were and how they interacted and spoke about the jobs they did when they returned from the day's work and remember thinking that I'd love to be a part of that. Once you become part of such a tight-knit group like arborists are it really grabs you with a kung fu grip.

OMC: Has tree-climbing technology improved since you started? How dangerous is the activity. How many times have you been injured?

MC: Has it ever! Everything has been advancing at such a fast pace, especially over the last 15 years or so. Gear is more comfortable, ropes are lighter, even chain saws are lighter and more user friendly. I just picked up a chain saw, the STIHL MS 192 T-C-E that is so light that I hardly feel it on my harness. And when you are pruning a 120' tall Oak tree, the EASY2START option reduces fatigue like you wouldn't believe.

The industry as a whole is still inherently dangerous; however, proper training and a continued respect for the risks involved can mean a long, injury-free career for those that take things seriously. I have had my share of injuries through the years, but nothing too serious. I still perform at a very high level. Fact is, I still hold world records in certain events at the International Tree Climbing Championship (ITCC).

OMC: Many homeowners tend vigorously to their lawns and gardens, but leave the trees alone. Do you have any tips for those people as far as what kind of care is important for the health of their trees?

MC: A sad reality for some is that a thick, green lawn is more important than a 100-year-old shade tree towering over their property. Call me biased, but I don't share that perspective. Trees need proper care to remain as vigorous as possible and even to limit the hazards that can develop. I always say that you need to look up once in a while. Look for large dead sections, broken or hanging limbs that can become dangerous to you and your belongings. Also try to seek out the local pest and disease alerts in your region. You could have a detrimental problem in your area that could be prevented with the right precautionary steps.

OMC: What are most common mistakes / wives tales about pruning trees?

MC: Here is an in-depth reply to this "somewhat" loaded question:

There are many "myths" about tree pruning that can confuse even the sharpest consumer.

Myth one: "Topping a tree makes it safer" -- As a professional arborist, I am frequently asked to top or reduce a tree's height to prevent it from failing in a storm. This may temporarily help reduce the chances of failure; but it will also create more long-term problems for the tree and its surroundings -- some that may not be correctable. Topping a tree reduces its ability to produce energy through photosynthesis. It also creates large zones of decay in the upper portion of the canopy. It will trigger re-growth that is denser, grows at a faster rate and is attached more weakly than their parent stems. All of this adds up to more maintenance and liability. Topping is a severe practice that should be reserved only for extreme circumstances.

Myth two: "Severe pruning invigorates a weak tree" --
This myth likely yields from the thick, dense foliage that often grows after severe pruning is performed, perhaps making the tree more beautiful than it's ever been -- and then it dies the next year. How can this be?

Trees store energy in many of their cells for later use. When a tree becomes distressed to the point that it is balancing on the fence of life and death, it draws on this stored energy as a last attempt at life. The stored energy is mainly used to produce more leaves that are often larger and greener. The trees do this to try to produce more energy. If unsuccessful, the tree then has zero resources left to draw upon and dies.

Myth three: "Tree paint should always be used to seal a cut." -- In most cases, tree paint should not be applied after pruning. Studies have shown that tree paint or sealant does not increase a tree's ability to seal a wound or slow decay. Some have even been proven to be harmful to a tree and can even speed up decay by sealing in moisture and protecting decay-causing organisms from the elements.

Myth four: "Always prune in the spring (or fall)." -- Generally, if pruning is for cosmetic or routine maintenance, then planning according to best timing for a given tree type is the best path -- certain types of trees should only be pruned under certain conditions and certain times of the year. The exception to this rule is when deadwood is being removed or if a hazardous situation arises -- in which case safety becomes the primary factor.

Some tree types like Maples, Birches and Elms should not be pruned during late winter or early spring. Since sap flow is greater during this period, it may be unsightly or disruptive to an area of the yard. More importantly, certain diseases and insects also affect these tree types. Pruning during this time may increase vulnerability and elevate the impact of such afflictions.

Trees like the Crape Myrtle have been planted further north in climates that are stretching their ability to survive the cold winters. Pruning of live branches from October through December may reduce their cold hardiness.

Pruning of certain flowering trees like Crabapple, Flowering Cherry, Pear, Peach, Dogwood trees and others should be avoided after July. After that time flower buds become set and pruning will affect their survival and display for the following season. It is also usually recommended to not prune just before or during flowering as well.

Disease may also be spread through pruning at the wrong time of the year. For example, pruning a Live Oak in the spring and summer will pose a greater risk of it contracted and / or spreading oak wilt. If you are unsure of the type of tree you want to prune or what ailments may be a factor for your pruning, seek a professional opinion.

This is just a quick overview of basic pruning principles and there are many more variables and disciplines to learn before one could be considered a "pro." When in doubt, ask a tree care professional. Obviously, not every pruning job requires a professional and the savvy do-it-yourselfer can certainly try their hand at basic pruning around the yard and garden. When doing so though, please follow the instructions and heed the precautions in the manufacturer's instruction manual for any equipment you might be using! In general, whenever a pruning task requires aboveground work, a professional should be contacted.

OMC: You have assisted the USDA in scouting out the spread of the insidious Asian long horned beetle throughout the Northeast. Do you have any advice for Midwesterners who are bracing for an invasion by the Emerald Ash Borer?

MC: I would recommend that anyone that feels at risk to such a widely spread insect or disease agent to seek out the advice of a professional. You could contact an International Society of Arboriculture (ISA) Board-Certified Master Arborist (BCMA) , or ISA Certified Arborist or even go further and speak with a local Agricultural Agent from a respected college or university.

OMC: What kind of presentation can people expect at the Tree Care Industry (TCI) Expo? How do questions from the "experts" differ from those of the laypeople? Is there a vigorous exchange of information among experts in the field?

MC: The Tree Care Industry Expo is a great resource for professionals in Arboriculture and related industries. There are presentations delivered by some of the most respected experts from all areas of the Green Industry. It is where professionals go to learn and share their studies and experience for the betterment of the industry, or more importantly, the trees!

Questions that arise from other practitioners will tend to be more technical than a "normal" home / land owner. There is a certain terminology that is used between professionals that I doubt could be easily deciphered by even the most savvy layman. I almost always learn a new term or technique myself.

Drew Olson Special to OnMilwaukee.com

Host of “The Drew Olson Show,” which airs 1-3 p.m. weekdays on The Big 902. Sidekick on “The Mike Heller Show,” airing weekdays on The Big 920 and a statewide network including stations in Madison, Appleton and Wausau. Co-author of Bill Schroeder’s “If These Walls Could Talk: Milwaukee Brewers” on Triumph Books. Co-host of “Big 12 Sports Saturday,” which airs Saturdays during football season on WISN-12. Former senior editor at OnMilwaukee.com. Former reporter at the Milwaukee Journal Sentinel.