Plantering av tall och gran - Epsilon Open Archive

72
GEORG CALLIN ocH JAN-ERIK HANSSON
the SFI-hoe. Calibrations of the pulse rate/oxygen intake ratio were made on one
worker during walk at different speeds (fig. 12 and 13) so that the pulse rate
values from the ordinary work days for this worker could be approximately
expressed into the corresponding oxygen consumption. Complete results of studies
during the normal work days are given in table 1S. They may be summadzed as
follows.
According to the classification of oxygen intake, pulse rate and rectal temperature
worked out by Christensen (19S3), the planting maygenerally be labelled
as "medium heavy" or "heavy" work from energy point of view. There were no
essential trends of the work output changes-measured in seedlings per minuteduring
the course of a day. The sweating rate varied with the air temperature
from low values up to about half a litre per hour (fig. 14, 1s, 16 and 17). Comparisons
between work-days with only planting and days with combined spothoeing
and planting, in both cases using the SFI-hoe, are demonstrated in table
16. Paired comparisons were made on days with about the same elirnatic conditions.
According to the table, there were no appreciable differences in rectal
temperature and sweating rate. However, a slightly higher pulse rate leve! was
apparent on days with the combination work metl1od than on days when only
planting. was performed. Fig. 18 demonstrates planting work using the one-man
auger as campared to the use of the SFI-hoe. N o essen tia! differences were seen
in the physiological response to work but there was a definitely higher average
work output when the SFI-hoe was used.
In chapter 10 the biological results are dealt with. Discussing the results, it
should be noted, that the extremely dry summer of 19SS occurred immediately
upon or one year after the lay-out of the experiments. This may be the main
reason for the high mortality of seedlings in some cases. It appears, that planting
with spot hoeing gave nearly so % higher survival after 2-3 vegetation periods
than planting without spat hoeing. The survival will also be greater if larger
spats are made. The differences in survival, however, are not so great. Of that
reason, it may be advantageous to make rather small spots and lay out some
greater costs for a supplementary planting. On some locations, however, one may
for certain reasons, e.g. heavy weed growth, want to make !arge spots in order
to proteet the seedlings from being smothered.
As to the differences between various planting methods it appears that planting
with SFI-hoe and planting in open holes give about equivalent results in normal
years. In the extremely droughty year of 19SS the plantation results were better
with the SFI-hoe than with open hales. As far as other metl1ods are cancerned it
seems to be a tendency that auger planting, slantwise planting and dibble planting
give results slightly inferior to planting with the SFI-hoe and planting in open
hales.
In paragraph ros the measurements of the last leaders are accounted. The results
show that a method giving high survival, also gives thrifty plants.
In a special appendix an outline of a piece work has been made for planting
and supplementary planting with the SFI-hoe under varying degrees of difficulties.