FARGO, N.D. (AP) - Dry weather helped North Dakota farmers over the past week, but a shortage of propane and storage space has slowed the corn harvest, the U.S. Department of Agriculture's National Agricultural Statistics Service said Monday in its weekly crop progress report.

Farmers are waiting for high-moisture corn to dry in the field because of the propane shortages and a lack of available storage. And some grain elevators have been limiting the bushels of corn that can be delivered based on the amount that could be dried every day, the agency said.

Farmers and grain elevators use propane to dry crops that come off the field too wet to store properly so they don't spoil. Peak harvesting times usually are staggered throughout the Midwest, but that didn't happen this year, elevator operator CHS Inc.'s propane marketing manager said earlier.

A delayed start to the planting season, combined with September and October rains, increased propane demand that local suppliers weren't prepared to meet, Tom Lilja, executive director of the North Dakota Corn Growers Association, said earlier. Other factors include a larger corn crop this year and industry experts telling farmers earlier this year not to lock into propane contracts, citing potential price drops, he said.

Lilja could not be reached late Monday for comment.

North Dakota's corn harvest is about 78 percent complete, well behind last year's 100 percent but ahead of the 69 percent average, the USDA said. The state's soybean harvest is close to wrapping up because combines can now get in wet areas that were hardened by freezing temperatures. About 63 percent of the sunflowers have been harvested, which is well behind the 95 percent at this time last year and the 87 percent average.