There appears to be a misconception amongst homeowners that one cannot be considered a true horticulturalist until you have either manipulated, bonsaied or re-configured your first tree or shrub.
Upon doing so, I wonder how many people have been overcome with guilt after realizing they must be related to Edward Scissorhands. The first cut is the toughest. After much deliberation, perhaps a family conference or two, blood is finally drawn. As the saw touches the raw pulpy flesh of the fledgling tree, tears streaming down the face of the remorseful surgeon, there is no turning back. It's too late!
As the branch falls to the earth, the tears suddenly dry up and are replaced with a feeling of pride, power and oneness with nature. After the first gut-wrenching cut, the rest is easy, even enjoyable. Limbs are dropping everywhere, what production! A sight that would make a beaver's mouth water.
The truth is the best way to gain respect as a knowledgeable horticulturalist is to gain knowledge from reliable sources and put that information to work in your garden. I believe a true horticulturalist is concerned with procedures that won't harm plants (especially mature trees); enabling the urban landscape to survive as a complex, dynamic environment with many symbiotic relationships.
Correct plant selection is an important step to ensuring a healthy prosperous landscape. Trees play the most important role in creating desirable urban micro-climates. Utmost importance should be placed on their selection. Maturity size is an important consideration. Trees and shrubs should have ample space to grow to reach their desired size and form -- uninterpreted. If a tree has outgrown its living space, it should be removed and replaced with a more suitable variety. Proper planning could have avoided this problem from the start.
Limit pruning to removing only smaller branches that are diseased, broken, crossing or too close together (thinning). For proper healing, cuts should be pruned on an angle slightly above a bud. Larger, dangerous limbs should be handled by experts so there's no property damage or harm done to the tree.
Flowering shrubs should only be pruned with high-quality pruning shears. If a flowering shrub is topped or rounded (like a Lollipop) most of the flowering buds will be removed along with the newest, most succulent growth. With the flower buds toward the center of the shrub they get little light and may not survive. If a shrub is pruned from the inside (removing crossing, rubbing branches) it allows flower buds to grow and flourish. If a shrub is getting too big, a few of the most extreme branches could be taken back to the trunk each year. Plants should be selected for their form and not manipulated against their will. Our cities would be quite a dreary place to live if our citizens only had clusters of robotic stickmen and lollipops to provide us with inspiration!