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Tree & Shrub care

Mulching and Landscaping

During the growing season, many homeowners and landscapers apply mulch to trees and shrubs. Some of the benefits of wood mulch products are:

  • Keeps roots cool in the summer and warm in the winter.
  • Maintains soil moisture, reducing the need for watering.
  • Inhibits certain plant diseases.
  • Keeps damaging weed whackers and lawn mowers away from plants.
  • Improves soil fertility.

The guidelines for proper mulching suggest that mulch should be applied at a depth of 2 to 4 inches, and spread to the drip line—the outermost extension of the branches. In our cramped urban setting this can be difficult to achieve, so applying mulch as broadly as practical will still benefit plants.

Mulch can have a negative effect and should be kept away from the trunk of trees to prevent rotting and provide good air circulation. Applying a new layer of mulch each year creates a buildup that can block oxygen and moisture from reaching the roots. That “fresh” look can be achieved by turning last year’s application with a rake or pitchfork.

Another mulching mistake that can kill a tree is "volcano mulching." This describes mulch that has been piled up in the shape of a cone around the base of trees, in some cases a foot or more high. Raised retaining systems, which commonly include the installation of landscape blocks/bricks around the base of the tree and filled with soil and possible topped with mulch, are also not recommend. This type of landscaping has a similar effect of "volcano mulching."

The Chicago Tribune has featured guidance for mulching and landscaping around trees and shrubs.  Please click here to read the article.

Free Wood Chips

The Village regularly offers wood chips to its residents, which can be ordered by submitting a service request. Public Works can deliver full truckloads only (approximately 3 cubic yards) directly to your home. For smaller quantities, residents can stop by the Public Works garage at 45 Forest and take whatever is needed. 

Drought Survival Tips for Trees and Shrubs

Homeowners are urged to continue watering trees and shrubs due to continued dry soil conditions and a rain shortage. It is important to know that trees and shrubs will benefit from continued watering – even trees and shrubs that have lacked sufficient watering throughout the summer. Here are some drought-readiness tips from The Morton Arboretum:

  • Focus watering efforts on trees and shrubs – not grass. Grass goes dormant and will turn green again when water is available. Trees can die without water.
  • Depending on air temperatures, trees and shrubs need at least 1 inch of water applied every week to 10 days to cope with lack of rain. Larger, established trees have a wide-spreading root system and need not be watered as frequently, perhaps every 2 to 3 weeks. Let the top few inches of soil dry out between waterings to avoid saturation and to allow roots and soil organisms to breathe.
  • Water slowly and deeply so water percolates down into the soil, electing one or two deep waterings as opposed to several light ones.
  • Use soaker hoses and drip irrigation -- effective watering tools because they discharge even streams of slow, trickling water directly to the root zone beneath trees and shrubs. When combined with a 3 or 4-inch layer of organic mulch, plants can use nearly all of the water that's provided with little evaporation loss.
  • When watering small trees, let a hose run slowly at its base until the ground is moist. For large trees, let the hose run at various points around the tree's drip line – the imaginary line on the ground that encircles a tree's extended branches.
  • Water shrubs at the plant base and under the spread of branches until soil is moistened to a depth of 6 to 8 inches.
  • When using a sprinkler system, place a container nearby to measure when you have distributed 1 inch of water to the soil.
  • Prioritize watering, caring for newly transplanted trees and shrubs first, then those that have been in the ground from 2 to 5 years and have under-developed root systems. Next, water “specimen” trees or important trees, then all other plants.
  • Water strategically. Plants absorb more water in the early morning, before the warming sun can cause evaporation.
  • Avoid using fertilizer during drought conditions. Fertilizer salts can cause root injury when soil moisture is limited.

For additional information, visit www.mortonarb.org or call 630-719-2424.