%0 Research Notes
%T Effect of dwarf-shrub vegetation suppression on berry and mushroom yields on a drained pine swamp
%A Seppälä, Kustaa
%D 1978
%J Suo - Mires and peat
%V 29
%N 3-4
%U http://suo.fi/article/9480
%X The paper deals with berry and mushroom yields on a dwarf-shrub pine swamp site, drained in 1922—23. The experimental field was laid out 12 years ago, in 1966— 67, and its forty sample plots were randomly divided into the following four treatment groups:
— untreated (control)(1)
— dwarf shrubs killed-off (herbicide treatment)(2)
— NPK (14—18—10) fertilization (500 kg/ha)(3)
— dwarf shrubs killed-off + NPK fertilization(4)
Each treatment was thus replicated 10 times and the size of a sample plot was 0.08 ha.
The results of treatments on stand development have been published earlier (Saras-to & Seppälä 1977). The berry yields were inventoried three times during the summer. 1978, i.e. in the middle of July, beginning of August, and at the end of August.
The changes in the coverage of berry producing plants after treatments are shown in Fig. 2 and the amounts of berries suitable for picking and edible mushrooms found are presented in Fig. 3. It seems probable that the amounts of cloudberry (Rubus chamaemorus) and lingonberry (Vaccinium vitis-idaea) that were picked nearly equal the total yields and the amounts of blueberry (V. myrtillus) and bog bilberry (V. uliginosum) about four fifths of the total yield. The corresponding quantities of edible mushrooms were only a fraction of the total yield.
Eliminating the competition from dwarf-shrub vegetation has more than doubled the cloudberry yield, but reduced the yield of bilberry to almost nothing. Simultaneous fertilization and herbicide treatment have decreased the yield of lingonberry to about one half of that in the other treatments.
On nutrient poor pine swamps fertilization (NPK) seems to increase the yield of edible mushrooms.
It is noticeable that cloudberry can grow and produce berries on these kinds of sites for decades after drainage and that the dwarf-shrub vegetation has only slightly been able to reappear during 12 years after herbicide treatment, on the soil from which it disappeared.