Chicago Region Trees Initiative

How to Care for Trees

Find trusted information on selecting, planting, and caring for trees.

Content Detail

Trees need care to thrive in our communities, whether they are in our yards, along streets, or in schoolyards or parks. To grow strong, stay beautiful, and to reach maturity a tree will need attention and care from the time it is planted for as long as it lives.

In cities and suburbs, trees often have to grow in very stressful conditions—with their roots confined in too-small spaces, surrounded by pavement, and in poor soil that is compacted so it is difficult for air and water to reach their roots. Attention and proper care from people can make all the difference in whether such a tree survives and how long it lives.

Young trees need special care and frequent watering for at least the first two years after they are planted. Even big, mature trees that have been growing for decades need watering when the weather is dry, and should be inspected and pruned as needed to keep them strong.

Large, mature trees deliver the greatest benefits, such as providing shade, capturing air pollution, emitting oxygen, holding rainfall to reduce flooding, and making our neighborhoods more beautiful and healthier. As important as it is to plant trees, it is equally important to safeguard the big trees we already have.

Finding the Right Place to Plant a Tree

The first step in planting a tree is finding a place where a tree can thrive. Every tree needs:

  • Enough space for its roots to spread out in the soil
  • Enough space for the spread of its branches when it is fully grown
  • Sunlight, without being shaded too much by buildings or other trees
  • Soil that allows water and air to reach its roots

Different kinds of trees need or can tolerate different conditions, so you should find a species of tree that is suited to the conditions of your site.

To prevent problems later, make sure you are not planting a tree beneath or near a power line or too close to a building or other structure. If the site is small or there are power lines nearby, look for a kind of tree that is naturally smaller when it is fully grown.

Resources

Selecting and Planting Trees Handbook (The Morton Arboretum) Learn how to assess your site and choose an appropriate kind of tree.

All About Soil (The Morton Arboretum) Learn about different soil types and how they affect trees’ growth.

Soil Tests, Site Considerations, and Changing Gardens (University of Illinois Extension) Learn how to understand the conditions of your soil.

Urban Soil Primer (Natural Resources Conservation Service) Get an introduction to urban soils.

The Power of Smart Planting (ComEd and The Morton Arboretum) Prevent problems by choosing a site and a tree that will not interfere with power lines.

Choosing a Tree for Your Site

Once you understand the conditions of your planting site, you need to pick the right kind of tree for the site. It’s very important to match the kind of tree you choose to your site’s conditions.

At the same time, consider planting a kind of tree that isn’t common nearby, to add species diversity and make your community’s canopy more resilient. A community that has too many of the same kind of trees risks losing them all to a new insect, disease, or climate problem such as drought. The best defense is to plant many different kinds of trees, so that some of them are likely to survive whatever comes their way.

Use the tools below to make the best decision for your site, or seek tree selection advice from The Morton Arboretum’s Plant Clinic.

Resources

Search Trees and Plants (The Morton Arboretum) Use the Arboretum’s website to choose the right tree for your site by filtering for your site’s sun, moisture, and size restrictions. Native trees and plants are also identified.

Right Tree in the Right Place (Arbor Day Foundation) Find tips for selecting the right tree for your site.

Buying High-Quality Trees (International Society of Arboriculture) Discover guidelines for determining tree quality at time of purchase and for identifying problems with tree structure, roots, and injuries.

Nursery Resources (Illinois Landscape Contractors Association) Once you know what tree you’d like to plant, find a local retailer.

Video: Plant Clinic Tip: 6 Tips for Selecting a Healthy Tree (The Morton Arboretum) Learn how to choose the right tree among all the ones at the nursery.

Video:How Plant Clinic Tip: How to Choose and Plant Your Tree (The Morton Arboretum)

Watch a demonstration on what proper tree planting looks like.

Planting Trees

Planting a tree correctly is essential to the long-term health of the tree. Mistakes made during planting usually can’t be corrected after planting and can lead to the death of the tree.

A tree’s roots grow not deep, but wide. When planting a tree, the planting hole should be only as deep as the roots or the root ball, but it should be two to three times wider. The sides of the hole should slope up gradually, making it saucer- or bowl-shaped.

If the tree came wrapped in burlap, place it in the hole before you cut the burlap and wire basket. Once the tree is securely in the planting hole, cut away as much of the burlap and wire basket as you can. Make sure to cut away and remove all materials on the top and sides.

Center the plant in the planting hole. Keep it straight with the branches pointing in the direction you want them to grow.

Make sure the root collar, or area of the trunk that flares out near the soil line, is visible. The uppermost lateral roots should be just below the soil surface.

Backfill the planting hole with soil, gently filling around the roots to eliminate air pockets.

Resources

Planting and Transplanting Trees and Shrubs (The Morton Arboretum) Get step-by-step instructions for planting a tree properly.

Planting Details and Specifications (International Society of Arboriculture) Use this peer-reviewed set of details and specifications in AutoCAD, PDF, and Microsoft Word formats for the green industry.

Video: How Plant Clinic Tip: How to Choose and Plant Your Tree (The Morton Arboretum) See what proper tree planting looks like.

Avoiding Tree and Utility Conflicts (International Society of Arboriculture) Learn how and why to avoid utility lines while digging; learn why it’s important to choose trees with utility lines in mind. Check out these tips for avoiding conflicts.

Tree Installation: Process and Practices(Purdue Extension) This instructional guide provides photos and diagrams illustrating proper tree planting technique.

Watering Trees

Trees need water to survive and grow. Water needs to be in the soil, rather than sprayed on leaves, so the roots can absorb it. Because rainfall doesn’t always provide enough water consistently, trees need people to water them in order to thrive.

Regular watering is especially important for young, newly planted trees that have not yet grown enough roots to collect the water they need from the soil around them.

When rainfall has been scarce and the soil is dry, even large, mature trees need to be watered.

Resources

Watering Trees and Shrubs (The Morton Arboretum) Get clear advice for watering both newly planted and established trees.

Drought Care (The Morton Arboretum) Learn to care for trees during times of drought.

Video: Plant Clinic Tip: When to Water (The Morton Arboretum) Watch a video demonstration on when and how to water trees properly.

Mulching Trees

Spreading a layer of mulch over a tree’s roots is one of the best actions you can take to care for a tree.

Mulch is an organic material, such as ground-up or shredded wood or leaves, spread on the soil surface to protect roots from heat, cold, and drought, and to provide nutrients as it decomposes.

Mulch mimics the layer of leaf litter that falls every year in the forest. In the woods, trees’ roots live under many years’ accumulation of this organic matter. In our urban environments, we can imitate this natural leaf litter with mulch.

When applying mulch, it’s important not to pile the mulch up against the trunk of a tree, a practice known as “volcano mulching”. Piling mulch against the trunk can cause the bark to rot.

The purpose of the mulch is to help the trees’ roots just below the soil. Spread the mulch in an even layer 3 to 4 inches deep on the ground around the tree keeping it 2–3 inches from the trunk.

A wide area of mulch will have an additional benefit as it will create a protective area around the tree preventing people from damaging the tree with lawn mowers or string trimmers while doing lawn care.

Resources

Mulching Trees and Shrubs (The Morton Arboretum). Learn how to apply mulch correctly and avoid mistakes.

Video: Plant Clinic Tip: Mulching (The Morton Arboretum) See how to spread an even layer of mulch.

Caring for Trees All Year

After trees are planted, they need continuous care to reach their mature size and provide the greatest benefits.

Mulching and watering consistently will improve a tree’s health and give you a chance to check them for symptoms of stress, diseases, or pests, but pruning is sometimes needed, too.

Young trees should be pruned to the right structure so they will grow up to be strong. Mature trees may need to be pruned to remove branches that are weakened, broken, or decayed.

Pruning a large tree can be extremely dangerous and is not a do-it-yourself job. Don’t prune a tree yourself unless you can do it with both your feet on the ground. If you would have to climb a ladder to prune a tree, consider calling in a certified arborist. It’s also good to have an arborist inspect a big tree for problems every few years.

While doing lawn care, be careful to keep lawn mowers and string trimmers away from a tree’s trunk and away from any exposed roots in the ground. These power tools can create wounds in the tree’s bark that can kill the tree. A ring of mulch around the tree can be a buffer zone that keeps power tools safely away from the tree’s bark.

When you plan any construction nearby, be sure to protect the underground roots as well as the trunk and branches of a tree.

Resources

Trunk Wounds and Decay (The Morton Arboretum) Learn why damaging a tree’s bark is a serious problem and how to avoid it.

Watering Trees and Shrubs(The Morton Arboretum) Get clear advice for watering both newly planted and established trees.

Drought Care(The Morton Arboretum) Learn to care for trees during times of drought.

Avoiding Tree Damage During Construction (International Society of Arboriculture) Use these precautions to protect trees from damage on and near construction sites.

Caring for Trees Before and After Storms (The Morton Arboretum) Severe storms are becoming more frequent as the climate changes. Follow these tips to plan ahead and reduce the risk of tree damage.

How to Mulch Trees and Shrubs (The Morton Arboretum) Follow these guidelines to mulch trees and shrubs properly.

Pruning Evergreens (The Morton Arboretum) Learn how and when to prune evergreen trees.

Video: How to Care For Your Trees with Kim Kalosky (Forest Preserves of Cook County)

Pruning Young Trees (International Society of Arboriculture) Learn about pruning young trees to ensure structural integrity as they mature.

Video: Plant Clinic Tip: How to Prune Trees (The Morton Arboretum) See how to improve a young tree’s structure so it can grow up strong.

Tree Owners Manual (USDA Forest Service) Learn everything you need to know about caring for your tree from planting to maturity.

Plant Clinic (The Morton Arboretum) Call, visit, or email to receive expert advice and get answers to your questions.

University of Illinois Extension Plant Clinic Learn what disease is affecting your tree by sending in a sample for testing.

Hiring an Arborist

Tree work, such as removing broken or rotting branches or taking down entire trees, is very dangerous. Doing extensive tree work yourself or cutting corners on price can lead to higher expenses down the line. Hiring a certified arborist with insurance can save you money and trouble.

Certified Arborists are tree experts who have received considerable training through the International Society of Arboriculture. Often, arborists have degrees in forestry. To maintain their certification, they are required to attend regular training to keep up with the latest science and best practice of tree care.

Certified arborists have the training and expertise to treat trees for pests and diseases. Trying to treat tree problems with the wrong product or at the wrong time can be futile or actually harm the tree.

Resources

Find An Arborist (Illinois Arborist Association) This directory connects residents and landowners with certified arborists.

Hiring a Professional Tree Care Company (Tree Care Industry Association) Get guidance on picking the right tree care company to manage your trees.

Why Hire an Arborist (International Society of Arboriculture) Learn why hiring a certified arborist is the best choice for any tree work.

Caring for Trees in Your Neighborhood

The trees in your own yard are not the only ones that add beauty to your life and value to your property. Trees on public property need your help too.

Trees in public areas like parkways and parks are managed and cared for by your municipality. You can contact officials in your community and speak up for trees.

You can keep your community green by watering trees in the parkway when the weather is dry. Spread an even layer of mulch over their roots, without piling it against the trunk. Avoid damaging their bark with power tools such as lawnmowers or string trimmers. Encourage your neighbors to help.

If there are no trees, or there aren’t enough trees in your neighborhood, consider taking action. Call your local government or your alderperson and ask for trees to be planted on the parkway. Consider getting neighbors together to seek a grant to have trees planted, or encourage a local community group to organize a tree planting.

Resources

How to Speak Up for Trees (Chicago Region Trees Initiative). Learn how to get involved in advocating for trees in your community.

Tree Planting Tool Kits for Communities (Chicago Region Trees Initiative) Apply for a kit of tools and materials for community tree plantings.

Tree Care Door Hangers (Chicago Region Trees Initiative) Free door hangers in English and Spanish give simple tree care advice.

Tree Planters Grants (Openlands) Learn about grants awarded for tree planting in the City of Chicago and south suburbs.