As an avid walker I spend many hours walking the streets and roads around my town in southeast Michigan. I have also enjoyed many days walking in the woods in the parks across the eastern United States. After looking at thousands of trees in both the man made and natural environments I noticed how different the trees are. A tree in a park in the city that grew from a seed that fell on the ground many years ago is full and strong while the trees planted by the cities over the same period are stunted and thin with their bark falling off. But some of these man planted trees flourished for some reason. This article will try to shed some light on what we can do to give these trees every chance to survive a long life in a hostile urban environment.
Think about how plants reproduce and spread. The seeds fall to the ground and are blown by the wind or carried by birds and animals sometimes for thousands of miles. Most seeds just rest on top of the soil where they start to germinate. This is the most critical moment for the tree. The pulpy cells that grow into the ground are highly specialized for water, oxygen and mineral uptake. The tough fibrous cells that begin to grow up towards the sky will become the trunk, limbs, branches, leaves, flowers, nuts and seeds. The bark that is exposed to air will protect the woody trunk from insects and the special cells of the leaves will absorb carbon dioxide and sunlight giving off oxygen and storing the energy of the sun in the form of carbohydrates. This is why, when transplanting a tree, the depth the tree is set into the ground is so critical.
One feature you'll notice about trees that grow in place from a seed is the beautiful bell shape at the base of the tree at ground level. All varieties of trees have this taper where the roots under the ground give way to the trunk above. Look closely at the base of the bell and you will see how the root's smooth skin-like covering turns to the rough-craggy bark of the tree. At this level is where the seed fell to the ground and started to grow into the tree you see now.
You will need to go to a forest or any area where you know trees grew from seed to see how splendid the shape of a tree can be. Now go to any city park or along the boulevards of your town. What you'll see immediately is the trunk either looks like a telephone pole going straight into the soil or a huge ball of roots sitting half buried on the top of ground. Try to dig down to find the bottom of the bell, now estimate how deep the tree was planted in relation to the ground level. If the tree sits to high you can easily see how shallow the tree was planted by holding a straight stick level above the ground from the point where the roots turn to bark. We waste millions of dollars every year on trees that will not survive because of improper transplanting depth. A study was done in Philadelphia that found only 57% of the trees planted lived ten years or longer.
Here are a few things you and your city can do to increase the lifespan of your trees:
Locate the bottom of the "bell" and plant precisely at ground level
Maintain a mulch bed to greatest extent possible around the base of the tree
Wood chips are not mulch and contain few carbohydrates. Many wood chips are made from old industrial pallets. Leaves are where the food for tree growth is.
Use a mulching mower in the fall and grind all the leaves in place
Don't try to grow grass under your trees. This robs the tree of water and nutrition and blocks oxygen from the roots
Trees absorb oxygen through the roots near the surface of the soil so the ground around the tree should be aerated or turned over several times a year
Avoid berms in your landscaping. Water drains away and the wind blows the moisture out of the raised and exposed area
Plant in the fall when temperatures will not exceed 70 degrees for most of the day
Balled & Burlapped trees commonly have soil and material over the bell of the tree. Carefully remove the dirt to find the bottom of the bell
Consider "bare root" trees which are smaller but easier to handle, less costly, greater varieties available and have better root spread at planting
Large properties and city parks should consider over planting seedling then culling over the years. (The seedlings will have to protected from animals and lawn equipment)
These practices for tree planting are not expensive and in the long run will save many millions of dollars. Trees will also be healthier and provide beauty and shade while helping with water retention and improving air quality.
Be patient: "The true meaning of Life is to plant trees, under whose shade you do not expect to sit". ~ Nelson Henderson
The natural bell shape at the base of the tree can tell you so much about the long term health of a tree. At the point where the roots become the trunk is where many years ago a seed fell to the ground. It is critical to locate this point when transplanting a tree.
Think about how plants reproduce and spread. The seeds fall to the ground and are blown by the wind or carried by birds and animals sometimes for thousands of miles. Most seeds just rest on top of the soil where they start to germinate. This is the most critical moment for the tree. The pulpy cells that grow into the ground are highly specialized for water, oxygen and mineral uptake. The tough fibrous cells that begin to grow up towards the sky will become the trunk, limbs, branches, leaves, flowers, nuts and seeds. The bark that is exposed to air will protect the woody trunk from insects and the special cells of the leaves will absorb carbon dioxide and sunlight giving off oxygen and storing the energy of the sun in the form of carbohydrates. This is why, when transplanting a tree, the depth the tree is set into the ground is so critical.
One feature you'll notice about trees that grow in place from a seed is the beautiful bell shape at the base of the tree at ground level. All varieties of trees have this taper where the roots under the ground give way to the trunk above. Look closely at the base of the bell and you will see how the root's smooth skin-like covering turns to the rough-craggy bark of the tree. At this level is where the seed fell to the ground and started to grow into the tree you see now.
You will need to go to a forest or any area where you know trees grew from seed to see how splendid the shape of a tree can be. Now go to any city park or along the boulevards of your town. What you'll see immediately is the trunk either looks like a telephone pole going straight into the soil or a huge ball of roots sitting half buried on the top of ground. Try to dig down to find the bottom of the bell, now estimate how deep the tree was planted in relation to the ground level. If the tree sits to high you can easily see how shallow the tree was planted by holding a straight stick level above the ground from the point where the roots turn to bark. We waste millions of dollars every year on trees that will not survive because of improper transplanting depth. A study was done in Philadelphia that found only 57% of the trees planted lived ten years or longer.
Here are a few things you and your city can do to increase the lifespan of your trees:
Locate the bottom of the "bell" and plant precisely at ground level
Maintain a mulch bed to greatest extent possible around the base of the tree
Wood chips are not mulch and contain few carbohydrates. Many wood chips are made from old industrial pallets. Leaves are where the food for tree growth is.
Use a mulching mower in the fall and grind all the leaves in place
Don't try to grow grass under your trees. This robs the tree of water and nutrition and blocks oxygen from the roots
Trees absorb oxygen through the roots near the surface of the soil so the ground around the tree should be aerated or turned over several times a year
Avoid berms in your landscaping. Water drains away and the wind blows the moisture out of the raised and exposed area
Plant in the fall when temperatures will not exceed 70 degrees for most of the day
Balled & Burlapped trees commonly have soil and material over the bell of the tree. Carefully remove the dirt to find the bottom of the bell
Consider "bare root" trees which are smaller but easier to handle, less costly, greater varieties available and have better root spread at planting
Large properties and city parks should consider over planting seedling then culling over the years. (The seedlings will have to protected from animals and lawn equipment)
These practices for tree planting are not expensive and in the long run will save many millions of dollars. Trees will also be healthier and provide beauty and shade while helping with water retention and improving air quality.
Be patient: "The true meaning of Life is to plant trees, under whose shade you do not expect to sit". ~ Nelson Henderson
The natural bell shape at the base of the tree can tell you so much about the long term health of a tree. At the point where the roots become the trunk is where many years ago a seed fell to the ground. It is critical to locate this point when transplanting a tree.
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