PARIS (Reuters) - Unusually dry and warm autumn weather in western Europe could leave grains more vulnerable to a cold snap this winter in France and Germany and may already have led to some sowings being disrupted in Spain, analysts and crop experts said.
It was too early to predict potential losses and the arrival of rain and cooler weather in the coming weeks would ease the situation by strengthening plants, they said.
In France, the European Union's top grain producer and exporter, the warm autumn had raised the risk of plants growing too quickly while also creating disease and pest problems.
According to public weather service Meteo France, the September-November period was set to be the second-warmest since 1900.
"Winter grains are in full growth and are at a much more advanced stage than usual for this time of year because of the mild weather and a sowing campaign that was a bit swifter than usual," Jean-Charles Deswartes of crop institute Arvalis said.
"The result is that we're observing the development of diseases and the situation will have to be checked in spring," he said, adding that high insect levels were also being seen.
An abrupt fall in temperatures and the arrival of winter frost could also be a threat as the fast growth of crops meant they were less sturdy than usual, he added.
Temperatures are due to ease in the coming days in France while much of the country will also see rain from Thursday.
Dryness is not seen as a threat at this stage for grains, despite low recent rainfall except in the southeast, but significant winter rain will be needed to nurture plants and replenish groundwater levels, analysts say.
In Germany, the EU's No. 2 grain producer, there was greater concern that dry weather was starting to damage some plants.
"We are starting to get initial reports of dryness damage in parts of the country including the south west," one German analyst said. "Some parts of east Germany have not had significant rain since the harvest and concern is also starting to grow in the east about dryness damage."
"It is too early to talk about the details but dryness damage is a theme this year. It is amazing and I have never heard of dryness damage being a problem in Germany in November."
Low German rainfall are shown by shallow water on the Rhine and Danube rivers disrupting freight shipping.
"Generally there is increasing worry that grain plants are not especially well developed because of the lack of rain," another analyst said. "This lack of growth may not in itself reduce yields for the 2012 harvest but plants will be going into the winter in a weak state."
RAIN TOO LITTLE, TOO LATE IN SPAIN
In Spain, an unusually dry autumn has hardened soil and delayed planting of winter wheat and barley in import-dependent Spain's northern Castile-Leon grainbelt.
Rain has fallen heavily in the past two weeks in many parts of Spain, but farmers say it has been too little and too late. Irrigation reservoirs in Castilla-Leon have about 20 percent less water stored than a year ago.
"It seems clear that autumn sowing will end with less acreage than last year. There will be more acreage left over for spring sowing, looking more at legumes, oilseeds or directly set aside," a spokeswoman for the Asaja farmers' union said.
Britain has also seen a relatively dry past three months but crops there remained generally in good condition after warm conditions helped boost crop development.
"The dryness has caused some isolated issues but as a national crop I don't think it has caused any long lasting problems," said analyst Susan Twining of crop consultants ADAS.
"The driest regions are in the Midlands and the Eastern Region where they have had about 70 percent of normal rainfall (in September, October and November) and there were some problems with uneven and delayed crop emergence," she added.
In contrast, parts of Italy have seen heavy rain this month but this has not derailed the ongoing wheat planting campaign and farmers, encouraged by high prices, are expected to sow more soft and durum wheat than last year, farmers and traders said.
"According to first indications from seed sellers, more area will be sown for soft and durum wheat," Paolo Abballe, grain expert at Italy's biggest farmers body Coldiretti, said, adding it was too early to give more precise estimates.
The U.S. National Centers for Environmental Prediction forecast normal precipitation in most of France, Britain and Germany in the next week but far below average in Spain and Italy. http://wxmaps.org/pix/prec4.html