APPLICATION OF POWDER FERTILIZER SILVAMIX® MG IN THE FOREST NURSERY
In 1992 were carried out in Forest Nursery Center Krasne Pole near Rumburk (Czech Republic) the trials with 40 kgs of sample of the powdered fertilizer SILVAMIX? MG (N-8%; P2O5- 12%; K2O-5,0%; MgO-15%; producer ECOLAB ZNOJMO, Ltd. Czech Republic) which was applied at varying fertilization rates to different wood species (see Table 1) during comparatively late periods, i.e. to sowings and to "packaged" seedlings at the begining of June and in the latter of June resp. In the case of sowings the result was very good. Saplings grown on the trial plots were clearly higher, being also correspodingly strong in the neck and of apparently fair quality. Considering the time of fertilizer application in the case of packaged seedlings, the difference in height increments was not as marked but the quality of their appearance was improved.
Based on this experience a total of 15 tonnes of aforementioned fertilizer was purchased in 1993 with the objective to apply it to sowings of the year 1993 and to packaged seedlings (see Table 2). It is assumed that in 1994 the application will be extended to open-air nurseries, particularly to those designated for beech where a granulated herbicide Casaron G (Solvay-Duphar BV, The Netherlands) can be used for protection against weed. In other nurseries with spruce seedling material the use of this fertilizer is considered only after the problem of inter-row spraying with herbicides, naimly with Roundup (Monsanto Europe SA, Belgium), is solved since after the application of this fertilizer very rapid and etensive infest with weeds occurs on the fertilized areas and these have to be weeded several times in the course of a vegetation period. This year full-scale trial with the fertilizer in tabletted form will be carried out; these would be added at the rate of 1 tablet (10 g each) per pot simultaneously with the laying of seedlings into RCK pots (peat-cellulose made pots) , so that each seedling will have enough nutrients for its growth in the enveloping pot and, at the same time, sufficient amount of nutrients will remain after its replanting on a clearing, whereby also the losses during forestation will be reduced.
In 1993 the trials plots of 1992 were fertilized again and very good height increments were seen here. E.g. in the case of spruce 1/2 in nisula (special vessels made of PVC) packaging this increment of height was 25-35 cm and with the plain-rooted spruce 2/0 the increment was 17-22 cm. At the same time these increments were adequately strong abd had a sufficient amount of lateral buds.
A great advantage of this fertilizer is that it is absolutely inoffensive as far as the foliar area of sampling and seedlings is concerned, so that its application on leaves is problem-free even in foilcovered hothouses where the air moisture is rather high. A practical example was beech saplings when the fertilizer was applied at the growth stage of 2-4 leaves and larger amounts of the fertilizer got stuck between two leaves. Even after a month no sign of damage could be found on those leaves. The same was observed with spruce seedlings where several smaller fertilizer particles were adhering among the needle-leaves that did not show any sign of damage during the whole period of their contact with the fertilizer.
Another feature that may be rated among assets is the ability of the fertilizer to inhibit the growth of hepatica and to cause even its perishing in the case that the contact is more-extensive. As regards mosses, however, the same is not true, their growth is rather stimulated but they may be kept within tolerable limits without problems if 2% solution of copperas is applied afterwards. A further advantage is that the leaching out of nutrients is not as intensive and rapid as if liquid fertilizers, Cererit or NPKs are applied. Since this fertilizier is active for a prolonged period of time, we are applying only a half of the dose in the next year in order to prevent inadequate growth of the overground part to the detriment of the root system.
In spite of such intensive additional fertilization the saplings exhibit a good quality root system with extensive root barb growth.
Weeds begin to run wild one week after fertilizer application, after two-three weeks the effect of the fertilizer on saplings and seedlings begins to become evident and after five weeks the effect already is fairly marked as regards boths the appearance and growth. When the fertilizer is applied before the end of May (the earlier, the better), lignification of the yearÂ´s shoots is taking place in due time as well and thus a potentional damage caused by ground frosts at the begining of ctober can be avoided. Lignification of the shoots may be stimulated further by praying with a solution of PK-sol at concentrations of 1.0 and 0.5% for older seedlings and for the current yearÂ´s saplings, resp., the rate being 1 litre per square meter, applied in two terms: 1st- last decade of August and 2nd - end of the second decade of September. Humic acids (trade name Kadostim) may be added to the spray solution.
When the fertilizer SILVAMIX® MG is used regularly all the seedling material can be cultivated on a raw, non-fortified peat substrate and the period needed for producing seedlings capable of being replanted, e.g. in the case of spruce, may be shortened by 1 to 2 growth cycles when compared with conventional cultivation while the good quality of seedlings is retained.
Brief description of the technology of seedling material cultivation
The joint stock company UNILES a.s. Rumburk is disposing of 15 foil-covered hothouses 9 x 50 m each of the Olbramovice type in which a travelling irrigation system Dolimat mady by the Farming Cooperative Dolina in Uherske HradiÅ¡te (Czech Republic) has been installed. This enables a uniform diistribution of irrigation water according to several variants and makes it possible to mix with its different spray agents such as herbicides and liquid fertilizers. All of the needle-leaved tree sowings and most of the deciduous tree sowings are cultivated in these facilities. The needle-leaved sowings are used for planting in open-air nurseries at the stage 1/0 or 2/0 at the most (spruce-picea abies) or for packaging in RCK pots or nisulas (spruce, larch, pine, etc.). Saplings 2/0 that satisfy the standard for direct replanting are used for forestation (concerning mostly the pine-tree, in lesser extent larch and spruce). Deciduous tree sowings are used mostly at the age 1/0 for forestation (alder and maple 100 %, oak and linden 70%, beech 50% of the total amoount). The remaining quantity is mainly packaged in RCK pots according to the customerÂ´s requirements.
In the foil covered hothouses we are growing saplings in plastic crates (as used for vegetable and bakery products handilng and the like) filled with substrate. Spruce, larch, fir and, to a lesser degree beech, are cultivated in 10 cm deep layer of the substrate, whilein the case of pine, alder, maple, linden and most part of beech the substrate bed is 16 cm thick. This method enables seedlings to be handled more quickly and with a greater care. Seedlings designated directly for forestation are transported in these crates up to the clearings where they are taken out only immediately before being replanted. The crates with saplings and seedlings that are to be grown until the age 2/0 are removed from the hothouses when the seedling age reaches 1/0 and the crates are placed onto a gravelled area where the cultivation continues until the of 2/0. Hence the foil-covered hothouses can every year be used for new sowing. The total area of the gravelled plots provided with artificial irrigation system is 2.75 hectares. All the fertilizing was effected exclusively with the aid of liquid fertilizers which were rapidly leached out with the irrigation and thus the resulting effect was nothing like that as expected in accordance with the expended costs.
In addition we are cultivating seedlings in 12 open-air nurseries having a total area of 7.30 ha. Here spruce is grown predominantly whereas maple, ash-tree and beech are sown in a lesser extent.
Table 1: Results of Fertilization in 1992
|Wood Species||Age; Method of Cultivatin||Fertilizer Rate (g/m2)||Increments Fertilized (cm)||Increments Unfertilized (cm)||Middle Increments (%)|
|SPRUCE||1/0; sowing||160||10 - 14||7 - 11||33.3|
|SPRUCE||1/0; sowing||80||8 - 12||7 - 11||11.1|
|SPRUCE||1/1; nisula||160||4 - 6||3 - 5||25.0|
|SPRUCE||1/1; nisula||80||3 - 5||2 - 5||14.2|
|SPRUCE||1/2; nisula||320||4 - 7||2 - 4||83.3|
|SPRUCE||1/2; nisula||160||3 - 6||2 - 4||50.0|
|LARCH||1/0; sowing||160||15 - 19||11 - 14||36.0|
|LARCH||1/0; sowing||80||13 - 16||11 - 14||16.0|
|LARCH||1/1; RCK pot||200||14 - 20||10 - 16||30.8|
|LARCH||1/1; RCK pot||100||12 - 17||10 - 16||11.5|
|SPRUCE1||2/2; RCK pot||200||4 - 6||3 - 5||25.0|
|BEECH||2/1; RCK pot||200||8 - 10||5 - 7||50.0|
|FIR2||2/1; RCK pot||160||5 - 6||4 - 5||22.2|
|FIR3||1/1; plain-root||160||4 - 6||3 - 5||25.0|
1 Picea Pungens; 2 Abies cor.; 3 Abies alba;
1. The differences in the increments of seedlings are not too marked owing to late application
2. Because of considerable nutrients defficiency in the substrate the needles of seedlings were short and yellow; after fertilization the colour of needles turned to fair green
Table 2: Results of Fertilization in 1993
|Wood Species||Age; Method of Cultivation||Fertilizer Rate (g/m2)||Increments Fertilized (cm)||Increments Unfertilized (cm)||Middle Increments (%)|
|SPRUCE||1/0; Sowing||160||12 - 18||7 - 11||66.6|
|SPRUCE||2/0; Plain-root||160||8 - 18||3 - 6||188.8|
|SPRUCE||1/1; nisula||300||8 - 16||4 - 8||100.0|
|SPRUCE||1/2; nisula||300||7 - 15||3 - 7||120.0|
|SPRUCE1||2/2; RCK pot||300||6 - 10||3 - 5||100.0|
|LARCH||1/0; sowing||160||15 - 21||11 - 15||38.5|
|LARCH||2/0; plain-root||160||12 - 25||10 - 17||37.0|
|LARCH||1/1; RCK -pot||160||16 - 26||12 - 18||40.0|
|LARCH||1/1; nisula||140||15 - 24||11 - 18||34.5|
|PINE||1/0; sowing||160||12 - 17||10 - 15||16.0|
|BEECH||1/0; sowing||160||15 - 40||12 - 25||48.6|
|OAK||1/0; sowing||160||16 - 40||10 - 22||75.0|
|FIR2||2/1/2; PVC||200||8 - 14||4 - 8||83.3|
1 Picea pungens; 2 Abies cor.