In a natural forest setting, trees take care of themselves. Each fall the soil is covered with leaves providing an ample supply of mulch and eventual organics and nutrients. Often times urban soils are compacted, lack organics, and have restricted space for tree roots to grow. Trees and lawns did not evolve together, will not thrive together, but they can exist together. Many tree health concerns start with the area below ground that we cannot see. Good soil health generally equates to good tree health.
The Benefits of Mulching
- Lessens amount of watering needed
- Creates aesthetically pleasing landscapes
- Insulates the soil microclimate from colder winter temperatures and warmer summer temperatures
- Keeps mowers and weed trimmers away from the trunk
- Reduces amount of lawn area and eliminates competition from turf grass
- Breaks down into organics over time
- Helps suppress weeds
- Creates a more natural environment in unnatural urban landscapes
- Stimulates growth; mulched plants grow faster that non-mulched plants
Soil & Tree Healh Concerns
Nutrient Deficiency
When a tree is suffering from a nutrient deficiency, it does not always mean that the soil is lacking the nutrients. In certain soils types or in soils with high pH, some trees species cannot gain access to nutrients such as iron and manganese. Chlorosis (iron deficiency) is common with river birch, pin oak, and red oak. Manganese deficiency is common with red maple. These deficiencies can lead to stress, dieback and eventually tree death is severe cases.
Fertilization
Lawn fertilization is not sufficient to provide benefits to tree and shrubs. In urban soils, nutrients are often lacking because there is no process of organic matter breakdown. Most people remove leaves each fall and in doing so, remove a good portion of nutrients that could benefit trees. Prescribed deep root fertilization for trees can help them obtain nutrients that are lacking in poor urban soils. Fertilization and the addition of wood mulch around a tree’s root zone can help simulate some of the conditions of a natural woodland environment. The addition of organics while fertilizing can help increase soil health, which in turn will benefit tree health.
Proper Watering
Improper watering is the number one reason that new plants do not survive. Proper watering through a plant’s first year is the key to the establishment of new plantings. The time it takes to establish is directly related to the size of the tree (or plant). Newly planted trees that are larger will take a longer time to establish a healthy rooting system.
How Much Water?
Many factors impact how much watering will be required to help a plant establish. These factors include plant type, temperature, humidity, wind, soil type, and soil conditions. Soils should be kept consistently moist but not saturated. Plants in sandy soils will require more watering than plants in clay soils. Over watering (specifically in clay soils) can be just as damaging as under watering.