NAPERVILLE, Illinois, May 6 (Reuters) - Nearly two weeks of wet weather in the western U.S. Corn Belt have put most of the Crop Watch producers’ planting efforts behind schedule after what was an efficient start to the season, and more rain this week could prolong the delays.

Seven of the 11 Crop Watch producers report they have done no field work since about April 25 - or any at all so far this season - but one of those producers, in eastern Iowa, started planting in full force on Sunday. Crop Watch follows 11 corn and 11 soybean fields across nine U.S. states, including two each in Iowa and Illinois.

The three easternmost producers were in the field last week, though rains held planting progress in southeastern Illinois and Indiana to a slower-than-normal pace while relatively normal progress occurred in Ohio.

Several of the Crop Watch producers mentioned feeling anxious, frustrated or concerned by the slowdown and wetness. Soils that cannot dry out before planting may cause emergence issues. Heavy rains, especially in Nebraska, will cause some fields to need replanting.

Half of the 22 Crop Watch fields (six corn, five soybean) have been planted by Monday compared with 15 by the same date in 2021 and 2023. Only five were planted as of May 6, 2022. Two weeks ago, producers reported planting pace a bit ahead of normal, matching a Crop Watch best.

But now, nine of 11 producers say planting progress has slipped behind normal pace in their areas. Ohio is the only location where things are slightly ahead, and it is too early in North Dakota to consider efforts delayed.

Wet conditions are slowing field work in every location except Kansas, where dryness is the cause. Half-inch rains on Friday marked the first measurable rainfall in two months for the central Kansas fields. Only irrigated fields were worked in Kansas last week after they were pre-watered.

Just two Crop Watch fields were sown in the last week, including the Ohio soybeans on Wednesday. That is their earliest plant date in seven years of monitoring this field, besting the prior record of May 9, 2018.

The southeastern Illinois corn was planted on Saturday, the second-latest for this field in eight years after May 18, 2019. Heavy rains early on Sunday may have warranted an eventual, full replanting of this field, though the producer reports that all his other planted and emerged crops look very good.

Crop Watch producers were unsure when the remaining 11 fields would be planted as several days of drying may be needed following recent and upcoming rains, though one of the eastern Iowa fields could be sown on Monday. Many producers note that cloudy weather has slowed the drying process.

None of the Crop Watch producers expect this week to feature fast or even normal planting pace due to the forecast rains, which will be on and off over the next couple of days throughout most of the Corn Belt. Temperatures may be normal to cool.

U.S. corn planting was 27% complete as of April 28 according to the U.S. Department of Agriculture, ahead of the recent five-year average of 22%. USDA will be out with May 5 planting progress later on Monday. The date’s recent corn average is 39%, matching approximate trade expectations. Karen Braun is a market analyst for Reuters. Views expressed above are her own. (Writing by Karen Braun Editing by Matthew Lewis)