Fjölrit RALA - 15.12.2000, Blaðsíða 23

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harvest dates. On the other hand, the interaction between locations and varieties, the
interaction between locations and years, and the year effects were all significant. This means,
as for the timothy varieties, that which of them was better, varied with the year, but also that
the difference between these varieties was significant at least at one of these locations. It was
only in Kollaíjorður that Fylking was significantly higher yielding than Lavang. It is
interesting that the density of Fylking in Kollaíjorður increased from year to year and was
around 80% in 1999 while the density of Lavang and P. pratense had decreased. In
Upemaviarsuk the results were opposite to the results from Kollaljorður; Lavang yielded
more and appeared more durable under ice cover. Earlier results from Upemaviarsuk also
showed that Lavang was better at this location than Fylking. The results indicate that Fylking
is a more temperate variety resulting well in the winter-mild climate in the Faroe Islands,
while Lavang is a more arctic variety, doing well in the low-arctic climate of Upemaviarsuk.
From Table 19 it can be seen that Lavang grows faster than Fylking in early spring,
both in Greenland and Iceland. The results from 1998 in Iceland (Table 18) also show that
Poa pratensis yielded as much as P. pratense if harvested twice.
In a Nordic investigation (Norgrass) interaction of Phleum pratense and Poa pratensis
with location and years was calculated (Helgadóttir and Bjömsson, 1994). The result was that
the Poa pratensis varieties varied much more in yield between locations than did timothy.
The same trend was found in this investigation.
In another investigation (Bjömsson, 1993), timothy from variety trials in the Nordic
countries were collected in order to investigate the usefulness of available data for
establishing agroclimatic zones, e.g. for integrated variety testing between countries. The
results were divided into five intemordic zones, but results from Greenland and the Faroe
Islands were not included in this investigation. Iceland and the most northem parts of
Scandinavia as well as some areas in the middle, became one zone. Further comparisons
between the West Nordic countries are needed for such zone division.
Seida has a different growth curve than timothy. It grows fast in early spring and
should like Poa pratensis, be harvested twice (Table 18). Then it can yield as much or more
than timothy.
Seida did not tolerate the ice cover in Upemaviarsuk as well as the other varieties.
With this exception the persistance of Seida is good at all locations.