Developmental pruning, also known as young tree pruning, is the process of pruning young trees to develop good structure while they are still young. This type of pruning can pay dividends for generations, as one of the main ways that a tree dies prematurely is structural failure. Structural pruning practices were largely developed by Dr. Ed Gilman, emeritus professor at the University of Florida. Dr. Gilman has worked closely with Sam Hill Tree Care. He led several training sessions with our team, sharing his expertise on the intricacies of structural pruning. ## Why is Developmental Pruning Performed? Developmental pruning is performed to mimic the structure that trees develop in their natural environment. Most trees grow in forests and compete with neighboring trees for sunlight. For this reason, forest trees typically develop a single dominant trunk (called a "leader") that is tall and straight. In the absence of this competition, landscape trees are encouraged to grow horizontally rather than vertically. The resulting structure—a short, wide canopy with multiple competing leaders—is weak and prone to failure. Developmental pruning should begin as soon as possible to promote good structure. Ideally, the nursery will begin developing good structure before the tree even reaches your landscape, but unfortunately, this practice is not widespread among Texas nurseries.[^1] Developmental pruning is especially cost-effective when done in the early stages of a tree's life. Although structure can still be improved with later correction, it is more costly and rarely yields equivalent results. [^1]: Florida, home of structural pruning pioneer Dr. Ed Gilman, developed the Florida Grades and Standards for Nursery Plants in 2015. Nurseries may only sell trees graded Florida #1 or higher, so you know the tree you're getting is high quality. Unfortunately, Texas has no equivalent plant material standards, meaning nursery stock can be hit or miss. ## How is Developmental Pruning Executed? Developmental pruning involves pruning young trees every 2-3 years to develop and maintain good structure. Pruning is performed more frequently in the early life of the tree, but as it matures, the frequency can be reduced. Ideally, developmental pruning should start when the tree is planted and continue until it's about 25 years old. Your arborist will begin by examining your tree for any pre-existing structural problems and determining if corrective cuts need to be made. Next, our expert crews will make targeted pruning cuts according to those specifications. Finally, we'll continue to monitor and prune your tree regularly throughout its life. With a strong foundation established through developmental pruning, your tree will be more resilient against structural stressors like strong winds and storms.

Hedge rejuvenation is like a kitchen remodel for your hedges—it's a drastic, but sometimes necessary, method of overhauling old shrubs that have become overgrown and unwieldy. This process involves reducing the size of overgrown shrubs to maintain aesthetics, improve light penetration, and promote healthy growth. As with any major corrective action taken in your landscape, it's essential to have a landscape professional plan and perform these procedures. Improper pruning can cause irreparable damage to the plant. ## Why Do We Perform Hedge Rejuvenations? Hedge rejuvenations are typically performed when hedges have become unwieldy as a result of unchecked growth. The main reasons for undertaking a hedge rejuvenation are: - To reduce the size of overgrown trees and shrubs that have outgrown their space, blocking sidewalks, windows, driveways, or other features. - To improve light penetration inside the "shell" of the hedge by removing dense branches and promoting new growth. - To restore a natural form to shrubs that have been pruned into formal geometric shapes (topiary). ## How Are Hedge Rejuvenations Performed? The hedge rejuvenation process involves several key steps. First, your arborist will identify the basic limb framework of the shrub or tree. Then, we will prune out and remove excess branches to create holes and allow more light in. A moderate amount (about one-third to one-half) of old growth is removed each year for 2–3 years, with a focus on thinning density and reducing size. Due to the drastic nature of this process, hedge rejuvenations are typically performed over the course of several years in order to maintain aesthetics while promoting healthy growth. After rejuvenation, the hedges will be stronger, more appealing, and more manageable.

Mulching involves spreading a protective layer of material, called mulch, over the soil's surface. Mulch may be either organic material, such as wood chips or leaves, or inorganic material, such as rocks. ## Benefits of Mulch Done properly, mulching is a simple and effective way to promote tree health. It has many benefits, including: - Reducing moisture loss due to evaporation - Insulating the soil against extreme heat and cold - Choking out weeds - Improving soil fertility as the organic matter in the mulch decomposes, releasing nutrients - Protecting against "mower blight"—wounds caused by mowers or weed whackers that may lead to decay - Beautifying your landscape—many homeowners prefer the tidy appearance of mulched beds ## How to Apply Mulch Winter is a great time to mulch before the extreme heat and drought of summer sets in. Apply a moderate layer of mulch, 2–4 inches thick, over as much of the root zone as possible. At minimum, the mulch layer should cover a 3–5 foot radius around, but not touching, the trunk. A 10 foot radius is ideal. If possible, use organic mulch for its beneficial impact on soil fertility as it decomposes. ## Mulching Mistakes The main goal when mulching is to cover the radius of the root zone without covering the trunk. "Mulch volcanoes," excessive piles of mulch which form a cone around the base of the trunk, are the worst example of this problem. Applying mulch against the trunk may soften the tissue and exacerbate insect and disease concerns. It may also lead to stem girdling roots which compress the stem and degrade the tree's ability to take up water and nutrients from the soil. Avoid overmulching. Layers of fine mulch that are too thick may become matted and prevent air and water from penetrating into the soil. **Avoid dyed mulch.** The chemical dyes may leach into the soil as the mulch decomposes.

Structural pruning is the process of pruning trees to promote good structure and reduce the impact of structural defects. This type of pruning can pay dividends for generations, as one of the main ways a tree dies prematurely is structural failure. Structural pruning should only be performed under the guidance of a certified arborist. Like Dr. Alex Shigo, father of modern arboriculture, once said: > Pruning is one of the best things an arborist can do for a tree, but one of the worst things we can do to a tree. ## Structural Pruning 101 with Andrew <div style="padding-bottom: 56.25%; position: relative;"> <iframe style="position: absolute; top: 0px; left: 0px; width: 100%; height: 100%;" width="100%" height="100%" src="https://www.youtube.com/embed/Bl11fUVd8Io?rel=0" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture; fullscreen" ></iframe> </div> ## Differences from Developmental/Young Tree Pruning We use the terms "[developmental pruning](https://samhilltreecare.com/resources/developmental-young-tree-pruning/)" and "[young tree pruning](https://samhilltreecare.com/resources/developmental-young-tree-pruning/)" to refer to structural pruning performed on young and developing trees. Why make the distinction? Pruning young trees for structure is fundamentally different from pruning mature trees for two reasons: 1. Young trees are more resilient and can better tolerate aggressive pruning to achieve structural objectives. 2. Young trees are much smaller than mature trees, which makes them easier and less expensive to prune than large, established trees. Although the best results are achieved by pruning early and often, structural pruning is also very beneficial for mature trees and should not be neglected. ## Why Perform Structural Pruning? Structural pruning seeks to imitate the structure that trees develop in their natural environment. Most trees grow in forests and compete with neighboring trees for sunlight. Because of this competition, forest trees typically develop a single dominant trunk (called a "leader") that is tall and straight. Without competition from nearby trees, landscape trees are encouraged to grow horizontally rather than vertically. The resulting structure—a short, wide canopy with multiple competing leaders—is weak and prone to failure. ## How Do We Perform Structural Pruning? The specifics of structural pruning vary a lot depending upon the tree to be pruned. In general, these are the strategies we use to promote good structure: - Promote a single dominant leader (main trunk) by reducing or removing competing leaders. - Space out branches along the dominant leader to improve airflow and light penetration. - Suppress branches with included bark.[^1] - Reduce or remove branches below the bottom of the permanent canopy.[^2] - Take steps to correct deficiencies introduced by improper pruning practices, such as lions tail pruning. [^1]: Included bark refers to bark that forms inside the "union," or joining point, of two branches. This weakens the union of the branches and may cause the joint to fail when under stress. [^2]: Identifying the "permanent canopy" helps distinguish between branches worth retaining for long-term structure and others which may need to be pruned back or removed due to site constraints. Branches below the permanent canopy may be removed for various reasons, such as to reduce or remove branches obstructing the sidewalk. Developing trees need low branches for photosynthesis. After the tree has matured enough to tolerate losing them, these low branches may be removed.