Rit Landbúnaðardeildar : A-flokkur - 01.05.1967, Side 184

11. At Hvanneyri some trials were done on blending sand into peat
soil. 200—600 and 1200 m3 of sand were used per ha which gave an
increase in yield of 9 — 16 and 19 hkg/ha of hay respectively.
12. Experiments with grass seed mixtures have shown that mixtures
holding only few components (3—4) have given the best yields.
13. Trials liave been done on many different grass strains. The best
strains of each species are given below in the order of merit.
Timothy: The Norwegian strains.
Engmo and Boden, the Scandinavian strains Grindstad, 0tofte and
Botnia II, the British strain Scottish.
Festuca rubra: The Scandinavian strains Trifolium, Viking, 0tofte
and S-59 from Aberystwith in Wales.
Festuca pratense: Sv. orig. Sena and strains from 0tofte.
Poa pratense: Sv. Fylking, McDonald and 0tofte.
Trifolium repens: Morsö and S-100.
Trifolium pratense: Tannnisto, Alfasvede and Toten.
Comparative trials at Hvanneyri with Deschampsia and Festuca rubra
show, that Deschampsia responds better to small doses of fertilizer.
Trials at Hvanneyri and Reykhólar show that of five various grass
strains (P. pratense, F. rubra, Alopecurus pratense, Timothy and Agrostis
Stolonifere) Timothy gave the biggest yield with doses of N P K.
14. Trials on croprotation which are to expand over 24 years were
started at Hvanneyri in 1957.
Experiments at Sámsstaðir on number of cuttings of hay fields show
that two cuttings (15th of July and lOth of Sept.) give the maximum yield.
Comparative trials have been done at all experimental stations on the
efíects ofNPK spred early in May (I) and late in July (II).
At Reykhólar and Skriðuklaustur the yield from (II) was only 50%
og the yield from (I).
At Akureyri the yield was 60% and at Sámsstaðir 75%.
15. Trials have begun at Hvanneyri to investigate the influence of
traffic on the yield of new hay fields.
16. Many varieties of consumer potatoes have been tested, but success-
ful crops have not resulted because of summer frosts, except for the year
1961.
The Russian variety Sibinskji Morozostoikji, which was expected to
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