SOIL DEGREE DAY ACCUMULATION FOR NEMATODE CONTROL 
RUSSET NORKOTAH, SLV RESEARCH CENTER - 2008
For root-knot nematode control, Vydate applications should begin at 800 Degree-days (DD5Celcius)
or 1,440 DD41Fahrenheit.  To estimate that date, add the number of "Total  DD" on the day you planted
to 800 (or 1,440).  Where that value occurs in the "Total DD" column estimates the date on
which 800 DD5C or 1,440 DD41F will occur in that field.
Contacts for questions: Russ Ingham 541-737-5255
This information can also be found on the SLV Research Center Website:  
http://www.colostate.edu/Depts/SLVRC/disease/nematode.htm
These data were updated August 1, 2008
Data after that date are estimated using average temperature for the previous 7 days.
The last date when the Degree Days were updated is in bold.
HISTORICAL Avg. 
GROWING AVE SOIL DAILY TOTAL AVE SOIL DAILY TOTAL TOTAL DD41F 2002-
MONTH DAY DAYS TEMP - C DD5C DD5C TEMP F DD41F DD41F   2007 2006 2005 2004 2003 2002 2007
1-May 1 1 13.5 8.5 8.5 56.2 15.2 15.2   17.1 15 10 10 0 0 8.7
2-May 2 2 11.0 6.0 14.4 51.7 10.7 26.0   34 31 18 18 9 10 19.9
3-May 3 3 11.4 6.4 20.8 52.6 11.6 37.5   51 49 26 26 18 21 31.9
4-May 4 4 12.9 7.9 28.8 55.3 14.3 51.8   67.1 68 37 37 27 35 45.2
5-May 5 5 14.2 9.2 38.0 57.6 16.6 68.4   81.8 87 48 48 36 49 58.3
6-May 6 6 14.6 9.6 47.6 58.3 17.3 85.7   93.7 105 60 60 45 61 70.8
7-May 7 7 15.1 10.1 57.7 59.1 18.1 103.8   107 123 72 72 54 76 84.0
8-May 8 8 14.7 9.7 67.4 58.5 17.5 121.3   123 142 84 84 63 92 97.9
9-May 9 9 14.0 9.0 76.3 57.1 16.1 137.4   140 160 98 98 72 106 112.6
10-May 10 10 14.3 9.3 85.7 57.8 16.8 154.2   159 176 115 115 81 120 127.6
11-May 11 11 14.2 9.2 94.9 57.6 16.6 170.9   181 193 131 131 90 137 143.9
12-May 12 12 15.4 10.4 105.3 59.7 18.7 189.6   203 212 146 146 101 157 160.9
13-May 13 13 15.1 10.1 115.5 59.3 18.3 207.8   225 233 162 162 115 175 178.6
14-May 14 14 13.9 8.9 124.3 56.9 15.9 223.7   247 254 179 179 130 194 197.0
15-May 15 15 14.3 9.3 133.6 57.8 16.8 240.6   268 276 197 197 146 213 216.1
16-May 16 16 14.2 9.2 142.8 57.5 16.5 257.1   289 300 224 224 163 234 238.8
17-May 17 17 15.7 10.7 153.6 60.3 19.3 276.4   309 323 244 244 181 254 259.0
18-May 18 18 16.7 11.7 165.3 62.1 21.1 297.5   331 348 263 263 201 275 280.2
19-May 19 19 17.9 12.9 178.2 64.3 23.3 320.8   355 373 286 286 220 297 302.8
20-May 20 20 18.6 13.6 191.9 65.5 24.5 345.4   377 398 310 310 238 317 325.1
21-May 21 21 19.0 14.0 205.9 66.2 25.2 370.5   396 425 335 335 255 338 347.3
22-May 22 22 16.9 11.9 217.8 62.5 21.5 392.0   414 449 361 361 274 358 369.3
23-May 23 23 14.9 9.9 227.7 58.8 17.8 409.8   429 471 387 387 296 375 391.0
24-May 24 24 14.1 9.1 236.8 57.5 16.5 426.2   443 495 415 415 321 392 413.4
25-May 25 25 15.6 10.6 247.4 60.0 19.0 445.3   458 522 442 442 346 410 436.7
26-May 26 26 17.0 12.0 259.4 62.6 21.6 466.9   476 550 469 469 369 429 460.3
27-May 27 27 17.8 12.8 272.1 64.0 23.0 489.8   496 577 496 496 391 449 484.0
28-May 28 28 18.1 13.1 285.2 64.5 23.5 513.4   518 619 522 522 413 470 510.5
29-May 29 29 17.9 12.9 298.1 64.3 23.3 536.6   540 646 548 548 437 492 534.8
30-May 30 30 18.3 13.3 311.4 64.9 23.9 560.5   562 674 571 571 463 516 559.4
31-May 31 31 19.2 14.2 325.6 66.5 25.5 586.0   584 702 595 595 489 542 584.4
1-Jun 1 32 19.9 14.9 340.5 67.9 26.9 612.9   607 732 619 619 513 570 609.9
2-Jun 2 33 19.7 14.7 355.2 67.5 26.5 639.3   631 762 644 644 535 598 635.6
3-Jun 3 34 19.8 14.8 370.0 67.7 26.7 666.0   654 793 669 669 557 622 660.6
4-Jun 4 35 19.7 14.7 384.7 67.5 26.5 692.5   676 825 691 691 578 641 683.7
5-Jun 5 36 18.8 13.8 398.5 65.8 24.8 717.3   698 858 714 714 599 660 706.9
6-Jun 6 37 17.2 12.2 410.7 62.9 21.9 739.2   721 892 737 737 619 681 731.3
7-Jun 7 38 18.7 13.7 424.3 65.6 24.6 763.8   742 925 762 762 639 702 755.2
8-Jun 8 39 19.7 14.7 439.0 67.4 26.4 790.2   764 950 784 785 659 726 778.0
9-Jun 9 40 19.1 14.1 453.1 66.3 25.3 815.5   787 973 803 809 681 754 801.1
10-Jun 10 41 18.7 13.7 466.7 65.6 24.6 840.1   812 998 823 833 704 778 824.8
11-Jun 11 42 16.4 11.4 478.1 61.5 20.5 860.6   837 1027 844 856 728 804 849.3
12-Jun 12 43 15.3 10.3 488.4 59.5 18.5 879.0   862 1059 864 880 749 829 874.0
13-Jun 13 44 16.8 11.8 500.2 62.2 21.2 900.3   883 1088 888 903 773 851 898.0
14-Jun 14 45 19.1 14.1 514.2 66.3 25.3 925.6   905 1114 914 927 795 878 922.2
15-Jun 15 46 20.4 15.4 529.6 68.7 27.7 953.3   929 1140 940 951 815 905 946.7
16-Jun 16 47 18.5 13.5 543.1 65.2 24.2 977.5   956 1164 968 975 838 928 971.5
17-Jun 17 48 17.2 12.2 555.2 62.9 21.9 999.4   984 1187 993 998 862 953 996.2
18-Jun 18 49 19.7 14.7 569.9 67.4 26.4 1025.7   1013 1215 1021 1022 883 978 1022.0
19-Jun 19 50 20.4 15.4 585.3 68.7 27.7 1053.5   1037 1247 1052 1045 907 1003 1048.4
20-Jun 20 51 19.3 14.3 599.6 66.7 25.7 1079.2   1066 1276 1084 1069 927 1029 1075.1
21-Jun 21 52 19.2 14.2 613.7 66.5 25.5 1104.7   1096 1303 1114 1093 946 1057 1101.4
22-Jun 22 53 18.2 13.2 626.9 64.8 23.8 1128.4   1120 1331 1139 1116 965 1085 1126.0
23-Jun 23 54 16.8 11.8 638.7 62.2 21.2 1149.7   1148 1357 1165 1140 984 1109 1150.7
24-Jun 24 55 16.4 11.4 650.1 61.4 20.4 1170.1   1179 1384 1191 1164 1005 1135 1176.1
25-Jun 25 56 16.3 11.3 661.3 61.3 20.3 1190.4   1210 1412 1214 1187 1028 1160 1201.9
26-Jun 26 57 16.0 11.0 672.3 60.7 19.7 1210.1   1240 1436 1236 1211 1051 1186 1226.7
27-Jun 27 58 17.1 12.1 684.4 62.8 21.8 1231.8   1265 1455 1262 1235 1072 1210 1249.9
28-Jun 28 59 18.0 13.0 697.3 64.3 23.3 1255.2   1292 1477 1287 1258 1096 1236 1274.4
29-Jun 29 60 18.6 13.6 710.9 65.5 24.5 1279.6   1320 1501 1309 1282 1121 1262 1299.2
30-Jun 30 61 16.7 11.7 722.6 62.1 21.1 1300.7   1345 1525 1335 1306 1144 1286 1323.4
1-Jul 1 62 16.7 11.7 734.3 62.0 21.0 1321.7   1373 1552 1361 1329 1169 1311 1349.0
2-Jul 2 63 18.1 13.1 747.3 64.5 23.5 1345.2   1404 1579 1385 1353 1193 1339 1375.5
3-Jul 3 64 17.5 12.5 759.8 63.4 22.4 1367.6   1435 1604 1411 1377 1219 1367 1402.1
4-Jul 4 65 17.5 12.5 772.3 63.5 22.5