Planting Native Trees is a huge contribution to the restoration and maintenance of native wildlife as well as biodiversity. Planting any trees helps to offset the deforestation and clearing of our land. The more trees we have growing on this earth, the better off we will be. In this article, you will be provided with a complete guide on choosing, planting, caring for, and maintaining the US native fruit, phytoremediator, and ornamental trees.
Table of Contents
Site Selection
Site selection is very important for the long-term health and prosperity of the tree. Some trees can adapt and grow almost anywhere, but choosing a good spot to plant for optimal, long-term growth is very important. Most trees prefer sunlight and deep, fertile soils, but trees can thrive in most areas as long as they are native to the climate. Choosing a tree that is native to your environment is likely the most important step.
One problem we often see with tree site selection is placing the tree where it looks nice now but not planning for its future growth. Far too often, we see very large trees planted too closely together so that they never reach their full potential due to crowding, or we see them planted too close to power lines or structures which means that someone will end up cutting them down long before they die of old age.
Having trees compete for resources is typically not a problem if you intend to replant a forest; that is the natural state, but some trees survive and thrive in the forest while others don’t. If you are paying for and planting trees in your yard, you probably want them all to survive, so you should take care to plant them in a suitable spot.
Consider their mature height and width. Some trees can be planted very close to one another, while others need room to spread out. For example, in the case of a fruit plant (apple, pear, peach, or pomegranate), you need to select a wide-open space to allow its canopy to spread. On the other hand, an ornamental tree such as a Palm tree or Sourwood grows erect, and the canopy is limited.
Steps to Planting a Tree:
1. Dig the Hole
- The size of the hole that you dig will depend on several factors.
- The size of the root mass of the tree you intend to plant. Always dig your hole at least one foot wider on all sides than the tree’s existing root mass(ball). This means that if you measure across the ball of the tree and it measures 2 feet, you should dig a hole with a 4-foot diameter. This will give the tree roots space to grow and make planting and leveling it easier for you. Of course, if you are planting a very small tree, you won’t need this much space. Do not dig the hole deeper than the ball of the tree; you need a firm, stable base that the tree will sit on.
- The type of soil that you are planting in. If the ground you are planting into is very sandy, gravely, and dry, you will want to make sure to plant the tree as deep as it grew in the nursery to maximize its ability to get moisture. If you are planting into heavy clay soils that will hold any water that flows into them, you will want to dig a more shallow hole so that part of the ball of the tree can be above the surrounding ground to allow it to get the oxygen that it needs.
- The moisture content of the ground you are planting in. How wet is the area? Regardless of the soil type, if the area is consistently wet, you may need to plant the tree a bit higher in the hole so that it can get the oxygen that it needs. Most dead, recently transplanted trees that I see have died because the tree was planted too deeply in the hole.
- The condition of the tree ball. Every tree has a depth in the ground at which it naturally grows. Tree roots don’t only take nutrition and moisture from the ground to feed the tree; they also need oxygen to grow. If the tree roots are planted too deeply in the ground, they will not have access to enough oxygen, and the tree will die as a result.
- It is always important to inspect the top surface of the root ball of a tree prior to its final planting. Where the roots grow from the tree’s trunk is called the root flare. The roots flare out from the base of the trunk. You must dig down gently to locate the root flare and the top of the roots to understand the depth at which your tree should be planted. Be careful not to scar the roots when you expose them.
- Most container-grown trees will not have this problem, but many balled and burlapped trees will have a thick layer of soil built up over the top of the tree roots. These trees are grown in a nursery where the rows are cultivated multiple times per year, which tends to push soil up onto the top of the roots. Then, when it comes time to dig the trees, more soil is piled on top of the roots, and the entire ball is covered with burlap. If you simply plant these trees at the height of the top of the burlap wrapping, many will be too deep and will die. It is not uncommon for a balled and burlapped tree to have 4-6″ of extra soil on top of the roots. The proper height of the tree is the most challenging and most crucial part of the planting. You cannot untie the twine or burlap from around the tree’s trunk until it is standing in the hole and you are done pushing on the tree trunk. Otherwise, you will push the tree right out of the root ball. So, for now, you need to give it your best guess.
2. Create a Dike
- As you dig the hole for your new tree, pile all of your excavations around the perimeter of the hole equally, and don’t step on them to compact them.
3. Put the Tree in the Hole
- Once the hole is complete, place your tree into the hole and stand it upright. If your tree is too heavy to lift, leaning the tree to one side and supporting the trunk as you roll the ball into the hole is a good way to get it where it needs to be. Use caution when placing and handling the tree, as it is easy to break branches and stems if mishandled.
4. Level the Tree
- Stand back and look at the tree from several different angles to ensure that it is planted straight up and down. Adjust the tree as necessary to make it appear straight from all angles.
5. Remove the Twine
- Once the tree is straight, and you are done pushing on the trunk, remove the twine and burlap from around the trunk and above the roots to ensure that the roots will be at the proper height. If the tree appears too low or high, you may need to re-wrap some of the twine or burlap to allow you to raise or lower the tree.
6. Backfill the Hole
- Once you are sure it is at the proper height, backfill the hole with a mix of organic material and friable soils from the excavation.
7. Finish the Dike
- Once the tree is backfilled, finish contouring the remaining excavated soils into a small dike around the hole that is slightly higher than the root ball and will help to hold in the water when you water the tree.
8. Water the Tree
- Next, slowly fill the hole with water, watching for areas where the water washes the soil down and causes a sinkhole. If this happens, add some more friable soil as you are watering to fill all sinkholes. Fill the soil ring up to the top of the dike and let the water soak in.
9. Mulch the Roots
Once the water has soaked in and there are no sinkholes, lightly mulch the top of the tree roots with wood mulch to help keep the soil and roots moist.
10. Monitor the Tree
- Monitor the tree for the next year by sticking your finger into the soil where the roots are. If the ground feels moist, the tree does not need any water. If the soil feels dry, the tree needs water, and you should once again fill the hole up to the top of the dike and let it soak in slowly. After the tree has grown for a year, it is not likely to need watering unless there are periods of drought.
Natural Soil Amendments:
Soil amendment is very important to improve drainage, water holding capacity, and soil nutrient availability. Amendments can be added to the hole as you backfill, along with some of the excavated soils. Amendments can also be added to the soils around the tree, outside of the hole, to encourage root growth. Always use organic soil amendments, as the chemical fertilizers are rapid action and less beneficial to long-term soil quality.
- Compost: well-rotten/partially decomposed organic matter of “Greens” and “Browns.” Greens include the grass, leaves, and food scraps to provide the “nitrogen,” while Browns include the woody remnants to make the compost “carbon-rich.” Compost nourishes the soil and provides spaces for the beneficial bacterial colonies to grow, die, and add humus to the soil.
- Sawdust: is a good soil nourishing material for acidic-soil-loving trees like Conifers, Rhododendrons, Blueberries, etc. It decomposes very slowly, so adding it to clay and moist soils will assist in speeding up the decomposition.
- Peat moss: is an expensive but very effective and compact natural amendment that lasts longer in the soil. It helps to improve the nutrient and water holding capacity of sandy soils while improving drainage in the clayey soil.
- Leaves: these are suitable for the entire yard. You can always add a layer of leaves over any garden to allow them to break down naturally and decompose, but if you want to use them for planting trees, it is recommended that you pile them with other organics and allow them to break down and begin to decompose.
Amendment of Problematic Soils:
- Poor/less fertile soils: urban soils are usually not very fertile, so they require some nutrient-rich organic treatment to improve the soil’s health and help increase the water-holding cation exchange capacity of the soil. Any of the above-listed organic amendments will help this type of soil.
- Silty soils: Unlike clayey soils, silty soils have severe water erosion problems in high rainfall areas. Removal of the nutritious layer of soil, larger deeper gullies, and exposed roots are the problems associated with silty soil.
- Solution: yearly addition of organic compost, leaf manure, or farmyard manure on the surface is good to avoid water erosion. Organic Mulching is the solution to silty soils.
- Alkaline/Acidic Soils: high and low hydrogen ion concentrations are problematic for plants. In highly alkaline soils, plants cannot absorb the nutrients, especially micronutrients, while in Acidic Soils, the trees would suffer from severe calcium, phosphorus, and sulfur deficiencies.
- Solution: Alkaline soil is treated with Gypsum/Lime solution to remove the exchangeable sodium ions with calcium. In Acidic soils, it will increase the soil pH and improve its cation exchange capacity.
- Heavy/Clay Soils: have compaction problems due to tiny soil particle sizes, resulting in poor drainage, oxygen depletion, dying of roots, and in the end, the death of the plant.
- Solution: It is recommended to add compost to the clay soils and to till it into the top 6 inches. Doing this every few months for a year before planting your tree would be a great way to loosen up the heavy clay soil. If you don’t have time for that, tilling organics into the clay around a newly planted tree will encourage root growth and help to break up the clay and improve the oxygenation of the soil. Depending on the density of the clay, cutting a smooth-sided hole, planting a tree, and backfilling with the organic matter may cause the tree roots to stay in the excavated hole as if it were a pot. The roots will simply circle due to the organic nature of the backfill and the density of the surrounding earth. This would not make for a stable root structure over time and is more likely to result in a root-bound, girdled tree. Breaking up the surrounding clay soils and adding organic matter, even if only in a few select areas, will get the roots started growing in the right direction and encourage the roots to penetrate the clay soil.
General Tree Planting Guidelines:
These are the general rules applicable to all types of tree planting:
- Tree selection: Type of tree (fruit or ornamental), its canopy size when fully mature, and sunlight requirement should be considered as tree planting is a long-term investment.
- Annual Nourishment: Add compost or kitchen waste (prepared by decomposing the daily kitchen waste) every year during Feb- Mar. No need to provide any synthetic fertilizer.
- Shaping/staking: every tree has its natural shape it attains when it matures. However, you can also choose to attempt to control the shape and size of a young tree through shaping and staking. Many professional tree planters will simply stake all newly planted trees, so they don’t need to come back to straighten a tree. For the tree’s health, it is better not to stake it as the movement of the trunk will help it grow deep and strong roots. The exception would be a tree that is very loose in the dirt ball, in which case it should be staked to prevent root breakage.
- Annual Pruning: When considering whether or not to prune your tree, it is important to ask yourself how much maintenance you want to sign up for. Most trees do just fine without pruning and can be left on their own to assume their natural shape. You can certainly choose to prune a tree to any shape that you would like, but it will add new growth every year, so keeping a particular shape or size will prove to be much work. In general, choosing a tree that is well suited for its location and allowing it to grow to its natural size and shape is the best scenario, both for the tree and you.
- Annual Mulching: Many landscape services try to sell their clients on the idea of freshening up their mulch beds every year by adding more mulch. Adding more mulch over a weedy patch of garden bed is a fine idea, but adding mulch on top of tree roots every year is not such a good idea. Always be sure to inspect the tree’s root flare before adding more mulch. You only want a very thin layer of mulch over the area of roots near the trunk. Thick mulch in this area may result in trunk rot and may encourage animals to live in the mulch and nibble on the bark. A couple of inches of mulch over the remaining tree roots away from the trunk is fine, but you surely don’t want it to be 6″.
Tree Planting Techniques and Types:
Container-Grown Plant:
Container-grown plants have been grown from either a tiny shoot or seed and are grown directly in the container they are sold in. This gives them the advantage of not having their roots cut when transplanted. You simply remove the tree from the pot, maybe loosen the root mass a bit if it appears to be root bound, and then plant it into the ground. These trees can be planted at any time of the year since they do not undergo root pruning at the time of planting.
Limitation: container-grown plants that have been in the container too long will have roots that are very tight in the pot and that can curve back around themselves and end up girdling other roots or the trunk. If you come across a densely packed root mass, loosen up the roots with fingers or a pruning tool before planting.
When removing a tree from a container, it is best not to pull and twist on the tree’s trunk to get it out of the container. It is better to lay the tree on its side and slide or cut the container off the roots.
Balled and Burlapped (B&B) Plants:
“Balled” for the “ball of soil and roots collectively” and “Burlapped” refers to the “material used for safely wrapping the plant balled area with.” The American Nursery Standards are the best standards for B&B. Balled and burlapped trees have long been the industry standard for larger tree transplants. Balling trees can be done by hand or with a machine. There are specialized machines that will dig out a tree and drop it into the burlap and wire sack to support it through transport and sale. Also, field workers will trench around the root mass of trees, tightly wrap them in burlap and then break them off of their pedestal, complete the burlapping and tie the ball in a criss-cross fashion with jute twine.
A properly balled and burlapped, hand-dug tree is a thing of beauty, and the quality can be felt by the tree’s stability in the ball and the tightness and precision of the burlapping. Machine B&B trees are fine but usually have a wire basket and are generally not as tight and well supported as a hand-dug tree.
In any event, the burlap will stay on the tree when planted as the burlap is biodegradable, and the roots will undoubtedly work their way through the material. Even wire basket trees will typically be planted with the basket intact, as this will tend to rust over time, but this wire basket may also prove to be somewhat detrimental to root growth. It is important to note that it is crucial to cut away any non-biodegradable twine that might have been used. Too often, with machine dug trees, you will find plastic twine used around the tree’s trunk. This will kill the tree over time if left intact, as it will not degrade.
Limitation: B&B plants can be moved only in the fall, winter, or spring when the transpiration rate is minimum, and the root growth is maximum. It takes about three years for the roots to establish correctly and start to regenerate to balance the root to shoot ratio.
Bare-Root Plants:
Easiest to plant, transplant, and least expensive are bare-root plants. Planted in the dormant season and staked as the landscape-sized bare-root plants are thin and elastic stemmed. This is a great way to get bulk tree saplings shipped to you very economically. Because they have no dirt, these tiny trees should be planted as soon as possible. Create a hole and hold the sapling at the correct level in the hole while it gets backfilled with a slurry of soft, friable topsoil and water, being sure to eliminate all air pockets as you work.
Environmental Benefits/Objectives of Tree Planting:
A mature leafy tree can produce enough oxygen for18 people to inhale throughout the year. The urban trees in the US produce approximately 61 million metric tons of oxygen annually, enough for two-thirds of the population of the US to inhale for the entire year. (Nowak, Hoehn, & Crane, 2007)
Plants absorb pollutants from the air, water, and soil as well. Either directly or indirectly, trees are helping in the removal of hazardous contaminants.
Plants absorb carbon dioxide, ozone, and other volatile organic compounds responsible for ozone layer depletion and global warming.
Trees’ extensive fibrous root system helps keep soil in place by minimizing soil displacement and preventing soil erosion.
Trees can be food sources for humans, animals, and wildlife and provide shelter to the animals; thus, they help conserve and increase biodiversity.
Trees are likely the easiest and cheapest way for us humans to reverse the climate change issues that our overpopulation and land abuse have caused.
Social Benefits:
At the start of spring, tree planting campaigns, projects, and activities become the source of building a community’s unity and spirit.
The experts arrange seminars school activities to highlight and remind the benefits of Tree Planting.
Plants improve mental health. Improves Mental health, stress and depression reduction, and psychological effects of plants are scientifically proved. (Kim, Lim, Chung, & Woo, 2009)
References:
Kim, W., Lim, S.-K., Chung, E.-J., & Woo, J.-M. (2009). The effect of cognitive behavior therapy-based psychotherapy applied in a forest environment on physiological changes and remission of major depressive disorder. Psychiatry Investigation, 6(4), 245.
Nowak, D. J., Hoehn, R., & Crane, D. E. (2007). Oxygen production by urban trees in the United States. Arboriculture & Urban Forestry. 33 (3): 220-226., 33(3).