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Figure
Prior to planting, bare-rooted seedlings should stand in a mixture of water and earth/clay for a few hours and containerized seedlings should be thoroughly watered. Excessively long roots (longer than 25cm) should be pruned with a machete or an axe.
Planting consists of the following operations:
- Digging of the holes;
- On-site distribution of the seedlings;
- Planting;
- Use of fertilizers (if required).
If the holes have not been made beforehand, the work may be conducted by gangs of two workers. The first digs the planting hole, the second distributes the plants and completes planting. On difficult sites more diggers than planters have to be assigned. Where holes are more easily dug, the ratio may be reversed. Another method is to let one worker distribute the plants to 10-20 planters who will dig the holes and plant. One single worker may also complete the whole operation of digging, carrying the seedlings and planting.
Planting techniques
Planting gangs of two
Planting in bigger groups
Planting
alone
Hoe an area of about 1 square metre around the planting holes. The area should be cleared of all vegetation to eliminate competition for nutrients and water. Dig the planting holes. Holes are required for all containerized plants and for big bare-rooted seedlings. The digging can be done at the same time as planting or some weeks in advance. If holes are dug before the rainy season, labour demand will not interfere with the agricultural season and the actual planting work will be faster. Even when the holes are dug in advance, the plantation worker should bring a hoe to be able to make the holes deeper or to adjust them.
For containerized forest trees the holes should be about 20-40 centimetres in diameter and slightly deeper than the length of the container. For fruit trees the hole should be larger (up to 60 x 60 x 60 cm). The harsher the site, the deeper the holes should be.
For bare-rooted seedlings make sure that the hole is deep enough to allow the taproot to hang down vertically without bending its tip.
Pile the soil on the sides of the hole without scattering it too much. Loosen, if necessary with a pickaxe, the bottom of the hole to make it easier for the plant roots to penetrate the soil.
On favourable sites small bare-rooted seedlings and cuttings may also be planted by just making a slot with a planting hoe (see 5.1).
Digging the holes
Hole for containerized seedling
Hole for bare-rooted seedling
Bigger hole for fruit trees
Tools required for digging
Normal agricultural tools are often not suitable for forestry work. Agricultural hoes, for example, have a wide, straight-edged blade and are heavy. They are therefore difficult to use on most tree planting sites. Suitable tools include the following:
An oval-blade planting hoe is the best planting tool for general purposes The oval blade penetrates the soil more easily than a blade with a straight edge. For containerized seedlings a hoe with a narrow blade can be used; for bare-rooted seedlings a hoe with a wider blade is preferable.
An open-angle hoe has an angle of 100-120° between the blade and the handle. The open angle makes it easier to plant bare-rooted seedlings straight, thus increasing productivity.
The "grubbing mattock" and the "planting mattock" have sturdy narrow blades with straight edges. They should be used if the planting site is stony and difficult.
A pickaxe which has one pointed and one narrow blade edge and a shovel can be used in hard soil when digging deep, big holes. The soil can be loosened with the pickaxe and removed with the shovel.
A wooden dibble or an iron bar can be used when planting cuttings. If loose soil is not available all over the site, extra soil has to carried for filling the holes. Dibbles or bars should only be used in sandy soil, which is not likely to become compacted.
Tools should be adapted to body sizes and for work in particular soils or terrains. The length of the handle should be adapted to the length of the worker. A hoe with a long handle is generally more efficient since it will allow work to be done in an upright standing position. When planting on a steep slope, it is preferable to use a short handed hoe to get a good work posture. Women and elderly workers should have lighter tools than fit male adults. The handle should provide a good grip, and an oval handle is preferable to a round one.
The edges of the planting hoes must be kept sharp with a file, to maintain them in good working condition. The handle should have an oval shape so that it does not twist in the hand. It should have a raised grip to prevent the hands from sliding off. Always keep the handle tightly fastened to the head.
Tools required for digging
Open angle hoe
Straight back planting hoe
Oval blade planting hoe
planting mattock
grubbing mattock
pickaxe
shovel
wooden
dibble
The supply of plants should be arranged so that planting is never held up for lack of plants. At the same time, the number of plants kept in temporary storage near the work site should be as small as possible.
Carrying seedlings is heavy work, especially when containerized seedlings with plenty of water-soaked earth are being carried. Appropriate tools for carrying should be available and work rotation used. Teams may change between, for example, distribution and planting work every 2 hours.
During planting, great care must be taken to ensure that the seedlings do not dry out. The roots should always be moist and never exposed to sunlight. This is especially important with bare-rooted seedlings. Seedlings whose roots are exposed to the sun for only a few minutes can already be seriously damaged and may not survive. Wet spongy material, for example grass, should cover the bottom of baskets, boxes or trays used for carrying the seedlings. With containerized seedlings the soil in the pot should always be moist at the time of planting.
If the distribution and planting of the seedlings is done by the same person, it is easier to ensure that the seedling will not dry out.
On-site distribution of seedlings
Figure
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Storage in the field as short a time as possible. |
Protect roots from drying out (e.g.
with wet grass)
Equipment required to distribute the seedlings on the planting site
When plants have to be carried long distances to planting sites, back-pack carriers or yokes should be used (described in section 3.5). When carrying seedlings on the site during planting, other types of carriers are preferable.
A shoulder-carried seedling container or basket will leave the hands free for planting. The harness should have a well-padded belt and shoulder straps. They should be adjustable to allow the weight of the seedlings to be distributed between the shoulders and the hips. A more comfortable model is a shoulder harness, with the trays or bags for seedlings hooked onto it.
A plant tray or a basket carried in the hand and put down on the ground during planting can also be used. Plant trays are especially useful for bare-rooted seedlings. Moist spongy material underneath and over the seedlings will protect the sensitive bare roots from drying out.
On-site distribution of seedlings
Shoulder-carried seedling containers
Bags hooked on harness, padded belt
and shoulder straps
Plant
tray
Planting containerized seedlings
When planting containerized seedlings, fill topsoil back into the hole until the hole is as deep as the container: Cut the container open with a knife or the edge of the hoe and remove the bag. Care should be taken not to break up the earthball. Place the earthball into the planting hole, the upper part of the ball should be slightly deeper than the surrounding soil surface. Put the remaining soil into the hole until it is filled to the rim.
Firm the soil carefully with your hands or with your heel. Do not leave air pockets around the ball or the plant will dry out and die. Check that the fuming is sufficient by gently pulling the plant. The plant should rest firmly in the ground.
Seedlings should never be left in their containers. It will restrict the growth of the root system and cause the death of the young tree some years later.
The most critical factor for all kinds of vegetation on dry to semi-dry land is access to water. After the hole is filled, a layer of loose soil is left around the plant. Shape the loose soil into a shallow depression. This will cause the surface water to concentrate around the seedlings and they will get as much water as possible.
Planting containerized seedlings
1. Fill soil back into hole
2. Place container in the hole
4. Back fill
3. Cut container open
5. Firm soil from two three
directions to remove airpockets
6. Make slight depression and mulch
where possible
Planting larger bare-rooted seedlings
When planting bare-rooted stock, put the seedling into the hole with the root collar 2-3 cm below ground level. The roots should be well centred. They must not be bent or curved and must never be allowed to get twisted or bent in the planting hole. If the tap root is too long it should be cut to about 20-25 cm. Put the soil back into the hole. Make sure that the seedling stands straight. At the same time sort out stones and green grass. Firm the soil with the heels or hands from two or three directions to remove air pockets. Take care not to damage the seedling.
Planting mistakes to avoid
Air around roots
Bended roots
Roots too shallow
Roots out of hole
Seedling not straight
Planting bare-rooted seedlings
1. Hold tree with root collar 2-3cm
below ground level
2. Put soil around the roots avoid
air pockets
3. Fill up the hole
4. Firm soil carefully
Planting cuttings
Branch cuttings should be about 35-45 cm long with at least two leaf buds in the upper 10-15 centimetres. They should be planted in a slanting position with about 3/4 of their length in moist soil. Care should be taken that they are not planted upside down. Planting cuttings upside down will delay or prevent the rooting process.
Stumps (also called root-shoot cuttings) should be 20-25 cm, about 80% root and about 20 % shoot. The diameter at the base of the stem should be between 1 and 3 cm. Stumps should be planted in a vertical position, with the root collar just at ground level.
All cuttings should be planted in premade holes. They should not be forced into the ground. Take care that cuttings are not planted upside down. Cover the upper cut with mud to protect it from direct sunshine.
For some species and on poor sites fertilizers may be needed. Manure can be used if only a few trees are being fertilized close to home. In plantations choose a well balanced complete chemical fertilizer containing nitrogen, phosphorus and potassium. If a chemical fertilizer is used, mix one tablespoon of fertilizer with the soil at the bottom of the planting hole. Direct contact between the roots and the fertilizer should be avoided as it would "burn" the roots. If 2,500 seedlings per hectare are treated with 1-2 tablespoons (about 20 grams) of fertilizer, one bag (50 kg) will be needed per hectare.
Planting cuttings
Planting branch cuttings
Planting stumps
1. Prune tap root and trim lateral
roots
2. Place stump in prepared hole and
fill up
3. Firm soil around stump. Allow 1-2
cm of shoot above ground.
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Common mistakes during planting Planting holes made too shallow. |
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