Planting conifers in coppice-forest
low reserves on deep soil (silt type trays)

This kind of problem occurs almost on a fairly frequent, because of current trends in forestry, to replace the hardwood thickets, abundant in much of France, by conifer plantations whose future is far more promising (Raper timber, poles, etc. ...). While we currently develop industrial facilities that can absorb increasing amounts of small hardwoods, but these products are bought up at very low (5 to 10 times cheaper per cubic meter, that small softwood good), and for foresters is to conifers plantation.

However, we must recognize that we lack accurate data to conduct such operations, especially since we used relatively broad non-native species growing called "fast", that we know enough of evil point of view of their light requirements. We can not - although this practice is sometimes - think raze coppice enrésiner because, besides the costs involved are very important (for the implementation of the first labor and maintenance required), this kind of transaction modifies a negative way sometimes, all factors microclimatic stations. So often, we practice tapes, or holes, which are installed by young conifer plantation high in the nursery (or where we simply sowing seeds), and this on only part of the forest. In this way we transform the original settlement, which in many cases may be perpetuated by natural means, much less expensive, the natural conifers plantation. This is obviously a long process, but a forester warned knows very well that any lasting work is subject to the constraint of inexorable time.

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Various opposing trends in relation to this type of operation, but it seems that, anyway, he agrees to provide to young seedlings, or seeding conditions favorable for Rr be assured that at least on this point, one of the conditions for good growth is completed.

 
 

FIG. 57 - Distribution theory of radiation on the ground in circular holes in strips of widths and different orientations. The shaded area corresponds to growing silver fir in the Jura, about 5% in its first year of growth up 25% at age 15 to 20 years) (Roussel 1962).


Figure 57 represents a form slightly different from that adopted at page 42 above, how Rr is distributed at various points of circular holes and tape, also defined as stated above, depending on the height of neighboring stands. These are, as we said well, supposedly very dense

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On the other hand, comments such as those related to page 93 above to determine the approximate area Rr suitable for each variety of each species used. For example, in Figure 57, lower part, was represented by the hatched area Rr which seems to suit the silver fir in the Jura (subject only been unusually warm and dry will come remove the majority of subjects). We see in this figure, the silver fir may be installed preferably in strips oriented north-south with a width equal to half the height of nearby bushes, supposedly adult (or often a wide 4 m in a thicket of 8 m in height), and on the south (facing north) strips oriented east-west, a width of some kind.

Here, however, for 12 species (or varieties) since 8 years experience, some general information on their location desirable depending on the type and orientation bands.

Douglas (race Sea) = Broadband (except in the south of the strip oriented east-west)
Norway spruce (Southern Alps) = d°
Norway spruce (Jura) = Normal bands (except in the south of the strip oriented east-west)
Spruce omorica = d°
Sitka spruce = d°
Japanese larch = Total found rapid
Corsican pine = Normal bands (except in the south of the strip oriented east-west)
Weymouth pine = d°
Nordmann Fir = d°
Silver fir (Aude) = d°
Silver fir (Jura and Vosges) = Narrowband - normal bands in the south, where east-west
Fir = Normal bands (except in the south of the strip oriented east-west)

 

When one considers the natural plant, by seed, in thickets interspersed with coniferous species old enough above (for indeed they were able to reproduce in the stations where they are installed), the most Simple will give the seedlings very quickly, a Rr 35%. which proved most beneficial to a range of subjects of various species (except for the silver fir in the Jura merely an Rr 20 to 25%, and Japanese larch, which requires a very fast Rr 100%). Examination of Figure 57 indicates that in a dense thicket assumed the Rr 35%. be achieved (in summer) center on the northern edge of large gaps (with a diameter of 16 m in size of 8 m in height, for example). In the south and the east and west sides, the Rr will be somewhat inadequate. But the subjects, usually quite "plastic" does not suffer too much. The presence in the soil, a sufficient water remains essential.