Ice-encasement and waterlogging damage in winter cereals and grasses in Finland
|Ravantti Saija, Miettinen Eero||B˙naarfÚlag ═slands, BŠndaskˇlinn ß Hvanneyri, Rannsˇknastofnun landb˙naarins, Rannsˇknast÷ SkˇgrŠktar rÝkisins, Tilraunast÷ hßskˇlans Ý meinafrŠi, Veiimßlastofnun||1989||ReykjavÝk|
Frß vefstjˇra: Greinina Ý heild sinni er a finna Ý pdf-skjalinu hÚr a ofan
Finland has been divided into four zones according to the risk of different types of winter damages. The agricultural statistics indicate that the winter damages in grasses and winter cereals occur predominantly in zones II and III, with ice, water and frost being the most common causes of injuries. From experiments it is seen that snow moulds, frost, ice encasement and waterlogging are the main causes of poor overwintering. Winter cereals and legumes were found to be less hardy than grasses.
Key words: grasses, ice-encasement damages, waterlogging damages, winter cereals.
Svellkal og drukknun ß vetrarkorni og gr÷sum Ý Finnlandi
Finnlandi hefur veri skipt Ý fj÷gur belti eftir kalhŠttu. Af landb˙naarskřrslum mß sjß a kal ß grasi og vetrarkorni er einkum af v÷ldum svella, vatns og frosta. Tilraunir sřna a rotkal, frostkal, svellkal og k÷fnun undir vatni eru aalorsakir kalskemmda. Vetrarkorn og belgjurtir eru ekki eins ■olnar og grastegundir.
Finland is the northernmost agricultural country in the world. Extensive cultivation of field crops is successfully practiced at latitudes between 60-67░N.
Finland's coastal regions have a maritime climate while the climate of the eastern and northern regions is more continental. Also the speed of winter's arrival varies significantly among the different regions. The thickness of snow and the duration of permanent snow cover varies from 110 days in the southwest regions to 160 days in Central Finland, and 190-210 days in Northern Finland (Kolkki, 1969).
With respect to the above mentioned meteorological factors Solantie (1985) and Rantanen and Solantie (1987) have divided Finland into four zones with reference to the risk of different types of winter damages (figure 1). The successful cultivation of winter cereals and grasses depends on these winter conditions.