* Australia wheat exports to slip in 2010-11
* About 40 percent of harvest expected to be downgraded
* Shipping berths booked out to end-April
By Bruce Hextall
SYDNEY, Jan 7 (Reuters) - Australia's wheat exports are likely to dip this year, after heavy rains left up to 40 percent the just-completed crop unfit for millers in Australia's major, quality-conscious markets, grain traders and analysts said on Friday.
A Reuters poll indicated an average of 14.24 million tonnes would be exported in the marketing year to Sept. 30, compared with 14.75 million in 2009/10 estimated by the U.S. Department of Agriculture in November.
The poll indicated a total crop of 23.37 million tonnes, up from 21.7 million in 2009-10, with estimates ranging from 22 million to 25 million tonnes.
But around 9.4 million tonnes of the crop could be downgraded to less than Australian Standard White (ASW) milling wheat to poorer-quality general milling wheat or feed wheat.
Australia, last year the world's fourth-largest wheat exporter, could become the third-largest exporter of the grain this year, displacing Russia which in August banned grain exports after a severe drought.
"The quantity will be there but not the quality," said Malcolm Bartholomaeus, a respected grain market analyst for Callum Downs Commodity News.
Western Australia, normally the country's top grain exporting state, saw its crop shrivel after its driest spring on record. It produced abut 4.4 million tonnes, , helped by improved grain varieties and some rain in its southern grain regions.
Still, the Western Australia harvest was nearly half the 8.2 million tonnes it reaped in 2009/10.
Dry weather also lifted protein levels in Western Australia, making its grain more popular to overseas buyers who acquire most of the state's wheat crop, said Steve Burt, head of Pentag Nidera, the Australian arm of privately owned Dutch firm Nidera.
Burt said lower-grade wheat would be harder to sell although a lack of grain out of the Black Sea region had opened markets and prices were nearly 50 percent higher than a year ago.
"The world is awash with lower-grade wheat, some of which will be used for animal feed, while the better grades will be used for milling even though it doesn't make the ASW standard, said Burt.
Grain shipping berths around the country are fully booked to end-April by which time about six million tonnes would have been shipped, he added.
Countries such as Bangladesh and Vietnam use lower-grade milling wheat while South Korea is a big buyer of feed wheat for cattle feedlots.
A greater issue is the lack of availability of higher protein in global markets because of production problems, including wet harvests in Australia's eastern state of New South Wales and Queensland, both key producers of high protein wheat.
Normally, around two million tonnes is harvested in these two states each year but analysts expect well less than one million tonnes has been reaped this season.
"One of the issues for the market is the lack of hard wheat as you do not get a lot of hard or higher-protein wheat come out of South Australia," said Paul Deane, an agricultural economist at ANZ Banking Group.
In New South Wales, a record crop of more than 12 million tonnes had been expected before torrential rains hit the crop during the harvest, which began late October.
But an estimated 2.5 million tonnes has been lost in that state, leaving about 8.5 million tonnes of ASW wheat and feed quality wheat.
Canada, another leading producer of high-protein wheat, has also battled wet, cold weather while the U.S. winter wheat crop faces the threat of frost-kill if a protective snow cover melts.
(Edited by Mark Bendeich)