Report about the research concerning fertilisation of spruce, beech and European larch forest stands and of individual and group plantations of sycamore maple and cembra pine with a slow release forest fertiliser SILVAMIX®MG in the territory o

This report presents results of a two-year research study concerning fertilisation of large forest plantations in the forest district Szklarska Pore ba with tabletted, slow release forest fertiliser SILVAMIX® MG (4 tablets per seedling) and represents a continuation of the contract research from years 1997-1998.

 

Attention was paid above all to principal mountain forest tree species, viz. spruce (Picea abies/L./Karst), beech (Fagus silvatica), European larch (Larix decidua Mill.) as well as to sycamore maple (Acer pseudoplatanus L.) and cembra pine (Pinus cembra). Research was carried out in forest soils characterised by a high acidity of the accumulation humus layer Ah where total pHKCl ranged from 2.8 to 3.2 and the content of nutrients was very low (most frequently: P2O5 - 0.5-1.5 mg/100 g, K - 3.0-5.0 mg/100 g and Mg - 2.0-3.0 mg/100 g; approximately a half of these contents occurred in the B layer. The degree of saturation with bases of the sorption complex Vh was low:

 

in the Ah and B layers, these values ranged from 3.0 to 5.0% (only rarely more) and from 2.0 to 4.0% (only rarely more). These soils were classified into the group of strongly polluted soils, especially with sulphur and aluminium. Contents of sulphur and aluminium in soil from the Ah layer ranged from 100 to 200 mg/100 g and from 150 to 200 mg/100 g, respectively. Deeper, i.e. in the B layer, the corresponding contents were 30 to 100 mg of S and 100 to 200 mg of Al per 100 g of soil.

 

As compared with controls, heights of young plants in forest plantations, as measured within the 1st and the 2nd year after the application of forest fertiliser SILVAMIX® MG showed dynamic annual increments and a better total height of plants as well as more dynamic annual increments in fertilised variants (Tabs 1 to 4).

 

The evaluation of the fertilisation effects was based above all on an analysis of correlations existing:

• Between percentages of average annual increments of experimental plants and of controls in the first and in the second year after fertilisation and between summarised two-year increments 1+2 and corresponding 1+2 controls (Tabs 1, 2 and 3 - columns 6 and 7);

• Between percentages of average annual increments and heights of original seedlings -h within the first year after the application of the fertiliser and in the first and the second year totally (Tabs 1, 2, and 3, columns 8 and 9) as well as of the resulting differences presented in the column 10 of tables mentioned above.

• Between relative average annual increments expressed as percentages of control variants and experimental test plants fertilised with SILVAMIX® MG in the second year after the application and corresponding increments recorded within the first year after the application (Tab. 4).

 

Results

Experimental results indicate a differentiation of fertilising effects derived from original heights -h of young plants after the application of this fertiliser.

 

Table 1 presents results of experiments carried out in spruce (average annual increments of experimental plants and controls in per cent). These results indicate a high efficiency of fertilisation of young plantations as early as 12 months after the fertiliser application and correspond with a 50-to-65-per-cent increase in the average annual increment (only rarely more) in smaller seedlings (initial height -h = 22.0 - 46.9 cm) and with a 35-to-45-per-cent increase of annual increment in higher seedlings (initial -h = 54.6 - 87.8 cm); in the second year after application , the annual increment was higher by several percent (however, only rarely by more than 10%) than in the first one. As compared with controls (annual increments 1+2), the average total increment after two years (annual increments 1+2) were higher by 50.8 - 68.9% and by 38.9 - 45.9%, respectively.

 

When evaluating the overall two-year efficiency of the forest fertiliser SILVAMIX® MG it is possible to say that the total height increase of smaller seedlings was very favourable and that better results were obtained in smaller plants than in higher ones as the corresponding heights ranged from 35 to 80% and from 20 - 25% in smaller and higher plants, respectively.

 

As compared with the first year, the fertilising effect showed usually a trend to a slight increase of several-percent (only rarely of several tens of percent). As compared with the growth dynamics of control plants, this increase was in average 4.3% (56.8% - 52.5% = 4.3%) in plants with a lower initial height -h, while in higher ones it was 6.9% (46.3% - 39.4% = 6.9%).

 

Table 2 presents results obtained in experiments with beech. Again, a higher efficiency of fertilisation was observed in smaller plants (with the initial height -h = 20.3 to 34.1 cm) where the annual increments ranged from 43.0 to 60.5% as compared with controls within the first year after the application. A relatively lower efficiency was observed in experiments with higher seedlings (with the initial height -h = 35.7 to 86.5 cm): the increase ranged from 31.7% to 34.8% and in the second year after the application the annual increment was higher by several percent than in the first one. As compared with controls (annual increments 1 + 2), the average annual increment after two years (annual increments 1+2) was higher by 45.3 - 62.3% and by 34.2 - 38.1%, respectively.

 

When evaluating the overall two-year efficiency of forest fertiliser SILVAMIX® MG it is possible to observe a very positive absolute height increase in smaller plants (from 31 to 70%) than in higher ones (from 16 to 22%).

 

Similarly as in experiments with spruce, also in beech plantations the fertilising effect slightly increased by several percent against controls (i.e. by 4.8%) in the second year after the application to smaller plants (82.4% - 77.6% = 4.8%); in case of higher plants, this increase represented 4.5% (56.5% - 52.0% = 4.5%).

 

Table 3 presents results obtained in experiments with larch. Again, a higher efficiency of fertilisation was observed in smaller plants (up to 54 cm); as compared with controls, the average annual increment of these plants ranged within narrow limits of 53.6-58.9% within the first year after the application. In experiments with higher seedlings (with the initial height above 57 cm), this increase ranged from 36.6% to 44.0% and in the second year after the application the annual increment was higher by several percent (only rarely by several tens of percent) than in the first one. This corresponded with average two-year increments of 57.0-68.7% and 41.0-46.9%, respectively.

 

When evaluating the overall two-year efficiency of forest fertiliser SILVAMIX® MG it is possible to say that the absolute height increase was very positive in smaller plants (45 to 70%) than in higher ones (24 to 32%)..

 

Similarly as in experiments with spruce and beech, also in this case the fertilising effect slightly increased (in average by 7.2%) in the second year after the application to smaller plants (44.6% - 37.4% = 7.2%); as compared with controls, in case of higher plants the increase was slightly higher than in experiments with spruce and beech (Tab. 4), viz. by 3.8% (41.4% - 37.6% = 3.8%).

 

In maple (two objects) the positive effect of SILVAMIX® MG was more marked also in experiments with higher plants because the average annual increment was higher by 41.1-58% than in controls. As compared with the first year, a slightly increasing tendency was observed also in the second one.

 

Cembra pine showed a relatively balanced response to the application of this fertiliser and its annual increment increased by 45-47% in the first year after the application. As compared with the first year, a persisting residual dynamics of growth was observed also in the second one (as compared with the first one).

 

Summary

When summarising the effects of application of a slow release forest fertiliser SILVAMIX® MG on the growth of seedlings after two years of experiments the following conclusions may be drawn:

 

1. In different localities of the forest district Szklarska Pore ba, fertilisation of forest plantations of spruce, beech and larch stands with SILVAMIX® MG showed a very favourable effect on the growth of plants and the following results were obtained within two years after the application (a sum of increments recorded in years 1 and 2): in lower spruce seedlings, annual increments were higher by 51-69% while in higher ones this increase corresponded with 39-46%; similarly, in experiments with beech and larch, the corresponding figures were 45-62% and 34-38%, and 57-69% and 41-47% respectively, as compared with the total increment of controls in the two-year experimental period.

2. In two-year experiments with spruce, beech and larch, the total efficiency of SILVAMIX® MG fertiliser application was manifested as a 40-to-70-per-cent and a 20-to-30-per-cent increase in the total height of smaller and higher seedlings, respectively (in spruce experiments by as much as 80%) as compared with controls.

3. Two years after the application of SILVAMIX® MG fertiliser to tree species mentioned above as well as to sycamore maple and cembra pine it was possible to observe a slight residual tendency to higher annual increments than in control plants. This indicates a cessation of fertiliser?s effect in all species under study in the third year after the application.

4. The obtained two-year results indicate a very important accelerating effect of fertiliser on the growth of young plants; experimental seedlings were able to overgrow the neighbouring forest weeds even in the first year and showed a more dynamic growth and a better canopy in years to follow.

5. When fertilising seedlings with SILVAMIX® MG it is recommended to apply this fertiliser earlier than one year after planting; this enables to reach a necessary rooting and development of the root system of baled seedlings.

6. After the application of SILVAMIX® MG fertiliser a marked deacidification of soil in close neighbourhood of young plants may be observed ; in layers of 0-10 cm and 15-20 cm, this decrease corresponds with 0.5 - 0.8 and 0.3 - 0.4 pHKCl, respectively.

7. After the application of SILVAMIX® MG fertiliser to young forest plants it is possible to observe a better chemical composition of assimilation organs (closer to natural one), especially an increase in levels of nitrogen and magnesium (e.g. in spruce, see Tab. 5).

 

Warsaw, 23 November 1998

 

 

Table 1

 

Annual height increments in forest spruce plantations in the forest district Szklarska PorÄ™ba ? results of research study on application of the tabletted slow release forest fertilizer SILVAMIX®MG

 

 

Table 2

 

Annual height increments in beech stands in the forest district Szklarska Poręba- results of a research study on application of the tabletted slow release forest fertilizer SILVAMIX®MG

 

 

 

Table 3

 

Annual height increments in European larch, Sycamore maple and Cembra pine in the forest district Szklarska PorÄ™ba ? results of a research study on application of the tabletted slow release forest fertilizer SILVAMIX® MG

 

Place Com- part- ment	Initial height of plants	Height two years after the application of SILVAMIX® MG	Average annual height increments after application (in the upper part after the first year, in the lower part after the second year)			(%) % of average annual increments (1+2) after SILVAMIX® MG in relation to control (1+2)	(%) Average annual increments as percentage of the initial height of plants- h (in the upper part after the first year, in the lower part after the second year)
			Control	SILVAMIX® MG	% of  control		Control	SILVAMIX® MG	Diffe- rence
	cm	cm	cm	cm
1	2	3	4	5	6	7	8	9	10
Forest district Ruczaj ? European Larch
340 b	57.3	114.3	15.0 23.8	21.6 35.4	44.0 48.7	46.9	26.2 67.7	37.7 99.5	11.5 31.8
Forest district Godzisz ? European Larch
4 d	53.9	122.0	19.2 24.0	29.7 38.4	54.7 60.0	57.6	35.6 80.1	55.1 126.3	19.5 46.5
Forest district Skalno ? European Larch
115 b	51.0	146.0	26.5 34.0	41.0 54.0	54.7 58.8	57.0	52.0 118.6	80.4 186.3	28.4 67.7
115 b	86.0	179.0	29.0 37.0	40.0 53.0	37.9 43.2	40.0	33.7 76.2	46.5 108.2	12.8 31.4
Forest district Szronowiec ?European Larch
310 b	51.0	115.1	16.6 24.2	25.5 38.6	53.6 59.5	57.1	32.5 80.0	50.0 125.7	17.5 45.7
310 b	41.5	104.0	17.2 21.1	27.3 35.2	58.7 66.8	63.2	41.4 92.3	65.8 150.6	24.4 58.3
324 a	41.6	106.9	14.6 24.1	23.2 42.1	58.9 74.7	68.7	35.1 93.0	55.8 157.0	20.7 64.0
365 b	83.8	155.8	23.2 28.2	31.7 40.3	36.6 42.9	40.1	27.7 61.3	37.8 85.9	10.1 24.6
366 a	69.4	139.9	19.9 30.0	27.9 42.6	40.2 42.0	41.3	28.7 71.9	40.2 101.6	11.5 29.7
366 a	78.9	168.5	27.8 36.0	38.8 50.8	39.6 41.1	40.4	35.2 80.8	49.2 113.6	14.0 32.8
Forest district Godzisz ? Sycamore maple
16 d	38.8	102.5	16.0 23.3	25.3 38.4	58.1 64.8	62.1	41.2 101.3	65.2 164.2	24.0 62.9
Forest district Kopaniec ? Sycamore maple
102 g	17.2	47.8	7.3 13.6	10.3 20.3	41.1 49.3	46.4	42.4 121.5	59.9 177.9	17.5 56.4
Forest district Skalno ? Cembra pine
115 b	28.7	57.4	8.6 10.8	12.5 16.2	45.3 50.0	47.9	30.0 67.6	43.6 100.0	13.6 32.4
115 b	46.9	87.3	11.7 15.4	17.2 23.2	47.0 50.6	49.1	24.9 57.8	36.7 86.1	11.8 28.3

 

 

 

Table 4

 

Dynamics of average annual height increments in forest spruce plantation in the forest district Szklarska Poręba- results of research study on application of the tabletted slow release forest fertilizer SILVAMIX®MG

 

 

 

Table 5

 

Content of nutrients in needles of one-year and two-year old spruce trees growing on research plots in forest district Szklarska Poręba- results of a research study on application of tabletted slow release forest ferilizer SILVAMIX® MG (averages are above, intervals)