Site preparation and the plant
Two of the factors that decisively influence the success of a good planting are the preparation of the ground and the choice of plant.
The preparation of the land
In general, for the planting of any forest species, it is necessary to first remove the existing competing vegetation from the plot to be replanted. It should be clarified that when dealing with land from a forest land consolidation scheme or from replantings carried out after a felling, no mature trees should be left in the area. This practice, much favoured by some Galician silviculturists, has no basis or future whatsoever, especially when adult trees are left scattered across the plot, mixed in with the new planting. These mature plants will be an obstacle to the good silvicultural practices that must be carried out in the plantation, they bend the stems of the new plants in their search for light and, in the end, they will have to be removed, which not only represents an added cost but also a risk to the new plants.
Mature pine trees in the middle of a new chestnut replantation. This practice is not advisable in Galicia.
Once the competing vegetation has been removed, the ground must be deeply softened by subsoiling. Subsoiling is the most common method of land preparation, as it is a cheap operation with a good effect. It is advisable to carry out the work along the line of maximum slope to make the task easier and to leave the planting in a more convenient position for future maintenance work.
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- Hand-made hole.
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- Combination of linear subsoiling on less steep slopes with trenching using a backhoe and a backhoe loader on slopes exceeding 40°.
And finally, especially on land abandoned for agriculture or on scrub-covered hillsides, it is advisable to carry out thorough cultivation or work the planting strips, preferably with a heavy harrow rather than a disc harrow, to encourage soil decompaction and suppress the regrowth of pre-existing vegetation.
If, due to excessive slope or risk of erosion, continuous subsoiling cannot be carried out, spot subsoiling or holes can be made with a backhoe.
In the case of flat land with some temporary waterlogging or drainage difficulties, it is advisable to open drainage ditches in a direction that facilitates water evacuation and does not impede mechanised work, and to construct sumps so that the plant's roots remain above ground level during the first years of establishment.
In the case of stony ground, when subsoiling stones may come to the surface that will hinder future work and spoil the appearance of the planting. To avoid this, the width of the subsoiling furrow can be reduced or it can be replaced by hole-making.
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- Drainage trench in an ash plantation.
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- Ash replanting where embankments were built to prevent waterlogging.
The choice of plant
The choice of a good seedling with genetic and morphological qualities suited to our land is essential for a successful plantation. The results of reforestation depend largely on the provenance of the seedling.
It is necessary to know the origin of the plant or seed in order to choose one whose origin most closely resembles the place where it is to be planted.
It is most common to use container-grown plants or bare-root stock. Sowing is rarely used and is only advisable if you want a dense planting at low cost.
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- Ash tree in a container.
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- Naked-root ash tree.
If you decide to use a potted plant, you should ensure that the pot's size is appropriate for the plant's size and age; otherwise, many problems will arise when it comes to rooting. The root should be balanced with the above-ground part (a straight, thick stem at the base) and properly positioned in the pot, with no root coilings.
The bare-root plant allows for rapid and extensive root system development and establishes with relative ease, but care must be taken to prune the roots (trimming them slightly) and position them properly in the ground so that they develop correctly. The main drawback is that it can only be used in winter.
American oak seedling thinned before planting.