|Special Public Works Programmes - SPWP - Planting Trees - An Illustrated Technical Guide and Training Manual (ILO - UNDP, 1993, 190 p.)|
|6. Maintaining plantations|
Even if the seedlings are of good quality, carefully planted and suitable to the site conditions, there will always be a number of seedlings which do not survive. Replacement or "beating up" is always expensive. Therefore it is necessary to decide carefully, whether replacement is required or not. This depends on the percentage of seedlings that died and on their distribution on the site.
Replacement will be necessary only if more than two in ten plants have died and only where at least two neighbouring seedlings have died. If the rate of failure is below 20 per cent, replacement will only have to be done if the failures are concentrated in particular areas of the site.
A method of establishing survival rates is described in Technical sheet 3. The survival count should be carried out at the end of the dry season following planting. Replanting is then done at the beginning of the rainy season that follows.
For replacement, big seedlings of the best quality should be planted at the beginning of the rainy season. If one person completes the whole replanting operation - carrying of the seedlings, digging the holes, planting the seedling - a minimum of time will be spent for walking and locating where planting is needed.
There might be a need for more than one replacement planting. But where after two replanting operations the area is still not adequately stocked, a thorough check is necessary as regards suitability of planting techniques, plant quality, weeding practices, choice of species and the quality of the work.
In the long run it is better to invest more in site preparation, planting and weeding than in replacement.
Less than 20% dead ® no replacement
Less than 20 % but concentrated ® replacement
More than 20% dead ® replacement
Common mistakes in maintaining plantations
Weeding too late.
Not continuing weeding long enough.
No, or insufficient, protection from grazing.
Protection from grazing and fire relies too much on technical means such as fences and firebreaks rather than on reaching agreement with the local population.