TRIAL DESCRIPTION AND SUMMARY The 1998 Uniform Regional Hard Red Spring Wheat Performance Nursery was planted at 18 locations and harvested at all locations in Minnesota, North Dakota. South Dakota, Montana, Wyoming, Washington, and Canada except Groton, SD (Table 1). Data were not obtained from Winnipeg, Manitoba as well. The nursery contained 28 entries and 5 checks. Trials were conducted as randomized complete blocks with three replicates. Yield data obtained from Morris and St. Paul, Minnesota, Powell, Wyoming and Pullman, Washington were not used in any of the over location averages nor in the stability parameter analysis. Data from each of 16 locations are given in Tables 2-1 to 2-16. The highest average yielding location was Powell, WY, with 87 bu/A and the lowest yielding location was 33 bu/A at Havre, Montana. The average yield of 13 locations combined was 50 bu/A, with, SD3348, ND691 and MN93413 in the first LSD unit which included the top 12 entries. Five entries, SD3310, SD3356, SD3345, NIN95002 and WA007824, were earliest to head at 22 days after June 1, while MN93413 was latest to head at 29 days. The entries within the first LSD unit for test weight were ND705, SD3345, MN95002, Keene, and ND694. Data for experimentals and checks grown for two years are given in Table 3-2. MN93413.ND691, ND695, N93-0119 and SD8119 were in the first LSD unit for grain yield. The highest test weight entries was SD3 )3 10 at 59.5 lb/bu. Stability parameters for entries in 1998 are given in Table 3-3. A lower b value indicates less responsiveness to changing environments for yield. A high Msq indicates lower predictability for yield and should be a warning that individual locations caused major deviation from expected performance caused by either disease or agronomic problems. Adult plant field reactions to stem and leaf rust are shown in Tables 4-1 through 4-2. Seedling stem rust data are shown in Table 4-3. Scab reaction from field inoculation in Minnesota and South Dakota is given in Table 4-4.