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Under the right conditions, planting trees helps restore damaged lands and provide firewood, timber, food for people and for animals, and medicine. Planting trees can make land that is poor and barren become rich and fertile again. But trees planted in harsh conditions need care to grow well. Tree planting has many benefits, but it is not right for all areas or all communities (see “Use everyone’s knowledge, consider everyone’s needs,” an activity that can help decide whether to plant trees). There are several ways to grow trees:
- Plant seeds or cuttings (pieces of a branch) directly into the ground.
- Collect and transplant wild seedlings.
- Grow tree seedlings in a nursery and then transplant them into the ground.
- Graft (attach) a cutting from a tree you want onto the root stock of another tree. (Grafting is usually used to grow fruit trees and is not covered in this book.)
The method you choose depends on what trees you want to plant, and what seeds or cuttings are available.
Selecting seeds or cuttings
Many people have sayings such as, “Like the parent, so will be the child.” Just as a child whose parents are tall will also likely grow tall, a tree seedling whose “parent” has a straight trunk that is good for lumber, or produces useful medicine, is likely to share those same qualities. It is best to collect seeds or cuttings from parent trees that are healthy and have the qualities you want. If you cannot collect seeds in your area, you may be able to get seeds from an extension agent, or from a nursery or garden in a nearby town.
Preparing seeds for planting
Some seeds, usually those with soft coverings and which are mealy or juicy, must be planted soon after they are collected. Other seeds may need to be stored for many months before you will plant them.
Most seeds need water to sprout. When a seed is covered with a thick or hard skin it may also need to be softened or cut before the water can soak in. Some seeds may need more treatment before planting.
- If the seed covering is not too hard (you can dent or break it with your fingernail) and not too thick (not thicker than the cover of this book), plant it directly into moist soil.
- If the covering is hard but thin, wrap the seeds in a piece of cloth. Let them soak for 1 minute in water that is too hot to touch, but not yet boiling (80 degrees C). Take them out of the hot water and quickly put them in cool water to soak overnight. Plant them the next day.
- Another way to treat seed coverings that are hard but thin is to soak seeds in cold water for 1 full day, then cover them with moist cloth sacks for another 24 hours. Repeat this procedure for 6 days. On the 7th day, plant the seed.
- If the covering is hard and thick, rub the seeds with a piece of rough stone or sandpaper until you see the soft, inside part of the seed. Be careful not to rub too deep and damage the seed.
- If the seed covering is soft but thick, cut a thin strip of the covering away from the soft inside of the seed, being careful to cut the seed as little as possible.
- Some hard-coated seeds are best treated by soaking overnight in water mixed with cow dung, then dried in the sun for 1 day. Repeat this process for 3 to 4 days. The good seeds will sprout and be ready for planting. The seeds that do not sprout can be discarded.
Some seeds need more complicated treatments, such as being heated in a low fire, chilled, or being eaten and passed by animals. Experiment to find what works best. After many attempts, you will be an expert at starting tree seeds.
Preparing tree cuttings
Some trees grow best by putting a cutting in the soil and watering it until it grows roots and leaves. Trees grown from cuttings usually produce fruit or seeds sooner than trees grown from seeds.
Some cuttings can be planted directly into the soil where you want the tree to grow. Others should be planted in a nursery until they have sprouted plenty of leaves and roots and can survive on their own.
Make cuttings from the middle of a branch where the wood does not bend too much but is not too rigid. Select a piece with about 6 to 10 “nodes” (bumps on the branch where the leaf grows or used to grow.) Gently remove the leaves, being careful not to damage the nodes. Cut the branch at an angle instead of straight across, to help roots form properly.
Whether the cuttings have been planted in a nursery or directly into the ground, be sure they have plenty of water and are protected from pests until they have grown enough roots to find water on their own.
Transplanting wild seedlings
|Collecting seedlings from the
forest to transplant
Another way to create a forest is to dig up wild tree seedlings and replant them where you want them to grow. Find healthy parent trees and choose seedlings growing near or under them.
Dig up small seedlings, careful not to damage the main, long tap root. If this root is damaged, the tree will not grow well. Dig in a circle around the seedling and as deep as you think the tap root has grown. Use your hand or a tool to bring the seedling up without shaking off the soil around the roots.
Keep the soil around the roots of the tree seedling moist until it is planted in the ground. Continue watering it until its roots have grown into its new place and it can find water for itself.
Growing trees in a nursery
Tree nurseries give trees a healthy start before they are transplanted to other places. But creating and caring for a nursery can be a lot of work. It makes sense to grow trees in a nursery when:
- The seeds or cuttings of the trees you want to plant are scarce.
- Pests would damage the young trees if they were not protected.
- People have enough time to take care of the nursery.
Planting trees directly is easier than growing them first in a nursery and transplanting them. However, many more tree seedlings die using the direct method than when you grow them in a nursery.
When to start trees
The time of year you plant will depend on how long the trees need to be in the nursery. If your area has a wet and a dry season, plant your trees just as the wet season starts so you will not have to water them as much. Most trees need 3 to 4 months in the nursery before they are big enough to plant outside.
Where to put a tree nursery
A nursery should be easy to get to and available for as long as it takes for tree seedlings to grow and be transplanted. It should also be accessible to everyone who will work there.
Every nursery needs these things:
Growing tree seedlings in containers
Growing tree seedlings in containers makes them easy to transport and to plant. Containers should be wide and deep enough to allow the seedling to grow a root ball, but not so big that they are very heavy or soak up more water than the tree will need.
The longer a seedling needs to be in the nursery, the bigger the container should be. A good size for most trees is about 6 inches wide at the top and 9 inches deep. They should be strong enough to stand upright when filled with soil, and have holes to allow excess water to drain out.
|Containers that will rot (newspaper, leaves, cardboard) can be planted directly in the ground along with the seedling. Containers made of plastic, glass, or wood must be removed before planting, but can be used again many times.|
|Dig square holes 1½ times as deep as the containers. Round holes prevent roots from reaching into the surrounding soil.||Fill the hole with soil so the base of the trunk will be level with the ground when the hole is filled. You may want to add a few handfuls of compost or rich, black soil to help the tree get started. After planting, soak the soil around the tree with water.|
Transplanting in difficult places
|In dry places, make small hollows
around trees to catch water.
Caring for young trees
|Make barriers to protect young trees.|
A tree needs to be protected through its first year of life. Many tree planting projects fail because no one takes care of the young trees.
If the weather is hot and dry, seedlings need to be watered first once a day, and then every 2 or 3 days. After a few weeks, the tree roots should find water. But if the weather is still hot and dry, water as the trees need it.
Cut back weeds until the tree is taller than the weeds. If animals or children might damage the young trees, construct barriers around the trees.
If a tree is not growing well, or the leaves look yellow or unhealthy, it may help to spread natural fertilizer in a circle as wide as the tree branches.