Trees may be far more low-maintenance than house plants or your garden roses, but they still have health needs which require specialist care throughout their lifetime. Many of these needs come from their foundation: the soil. Healthy soil is key to a healthy tree — sometimes tackling poor tree growth isn't about fixing the tree but rather fixing the ground beneath it. There are several issues to look out for in your soil, and one of the most common and damaging is soil compaction.
Soil compaction is the natural tendency of a patch of soil to become denser over time, simply to to the pressures of footfall above it and water drainage through it. This leads to compact soil which imprisons tree roots, leaving them unable to grow. If its roots are stunted, a tree will be unable to draw in adequate nutrition — the compact soil also means that less water will be able to drain through to the roots in the first place. If your soil is too dense to shovel by hand or showing signs of a crusty top layer, it may be compacted. This will also show in your trees: Those suffering because of soil compaction look wilted, dropping leaves from their canopy, and in serious cases losing tissues in their roots and trunk.
Regular mulching and avoiding too much foot traffic around your trees will help prevent soil compaction, but if the problem is already established you'll need to look for a cure. If you're concerned about soil compaction, speak to a tree service professional to assess your soil and find out how to make improvements. Businesses like Waratah Tree Services will even turn pruned branches or trees into mulch for you to use around your yard.
There are a few options for dealing with the problem depending how severe it is.
Aeration services will punch holes through to the root layer, allowing immediate access for water and air. Your local tree services will have the equipment and expertise to effectively aerate without damaging your roots. A similar option is vertical mulching. Again, holes are punches down to root layer but are filled with mulch. This creates a longer-term effectiveness and helps to build a looser foundation of soil than just aeration.
For more extreme cases, radial trenching can provide channels of loose mulch along which roots can grow. This technique involves digging down into the soil around a tree in a pattern like a bicycle wheel. The trenches can then be filled with aerating mulch. This not only helps the tree, but it also aerates and loosens the soil a great deal, creating a long-term solution to soil compaction.