WASHINGTON — Although the overall winter wheat condition rating as of April 20 was nearly unchanged from a week earlier and from a year ago, ratings in several key hard red winter states continued to slide, the U.S. Department of Agriculture said in its April 21 Crop Progress report.

Winter wheat was rated 34% good to excellent as of April 20, 33% fair and 33% poor to very poor, compared with 34%, 34% and 32%, respectively, a week earlier, and 35%, 32% and 33%, respectively, at the same date last year.

But good to excellent ratings slid in Kansas to 24% (26% a week earlier), Oklahoma to 11% (14%), Texas to 12% (13%) and South Dakota to 66% (67%), while improving to 68% in Montana (65%) and holding steady in Colorado at 36% and in Nebraska at 59%.

Good to excellent ratings improved from a week earlier in five of the seven main soft winter wheat states, declining only in Missouri and Michigan.

Meanwhile, crop development continued to lag, with 9% of winter wheat overall headed as of April 20, slightly ahead of 7% last year but behind 17% as the 2009-13 average for the date.

Spring wheat planting in the six major states at 10% completed as of April 20, also was behind the average pace of 19% for the date, the U.S.D.A. said. Spring wheat was 1% planted in North Dakota (10% average), 17% in South Dakota (32%), 5% in Montana (16%), 65% in Washington (55%) and 79% in Idaho (48%). Planting was yet to begin in Minnesota, well behind the 27% average for the date.