Pear Psylla Degree Days (updated weekly)
This page shows the cumulative pear psylla degree-days (DD) calculated by DAS at selected weather station
locations across the Pacific North-West as part of the integrated pest management (IPM) program
recently developer by the
WSU Entomology Pear Extension and Research group
at WSU-TFREC in Wenatchee, WA. The map below shows the most recently calculated cumulative DD values
at each location.
The DAS calculated pear psylla degree-days will be available for free to the public for the 2022 season.
Cashmere.N, WA | Hood River, OR | Medford, OR | Omak, WA | Peshastin.N, WA | Wapato.W, WA | Wenatch.W, WA | |
---|---|---|---|---|---|---|---|
Feb 28 | 56 | 114 | 296 | 6 | 48 | 92 | 55 |
Mar 7 | 99 | 162 | 336 | 25 | 78 | 146 | 95 |
Mar 14 | 123 | 198 | 388 | 40 | 95 | 183 | 123 |
Mar 21 | 165 | 234 | 429 | 72 | 124 | 226 | 167 |
Mar 28 | 253 | 326 | 535 | 140 | 201 | 315 | 259 |
Apr 4 | 311 | 380 | 596 | 192 | 246 | 377 | 323 |
Apr 11 | 351 | 413 | 656 | 232 | 273 | 417 | 365 |
Apr 18 | 363 | 433 | 683 | 247 | 280 | 431 | 381 |
Apr 25 | 427 | 488 | 742 | 301 | 331 | 495 | 453 |
May 2 | 493 | 548 | 807 | 362 | 383 | 559 | 531 |
May 9 | 572 | 620 | 875 | 439 | 442 | 642 | 624 |
May 16 | 650 | 703 | 961 | 508 | 505 | 734 | 713 |
May 23 | 747 | 797 | 1063 | 594 | 585 | 837 | 825 |
May 30 | 869 | 910 | 1185 | 711 | 682 | 949 | 958 |
Jun 6 | 1008 | 1062 | 1318 | 857 | 807 | 1106 | 1111 |
Jun 13 | 1151 | 1197 | 1472 | 999 | 936 | 1265 | 1274 |
Jun 20 | 1290 | 1323 | 1581 | 1135 | 1050 | 1400 | 1436 |
Jun 27 | 1477 | 1513 | 1779 | 1316 | 1221 | 1591 | 1644 |
Jul 4 | 1674 | 1687 | 1957 | 1505 | 1391 | 1800 | 1858 |
Jul 11 | 1868 | 1877 | 2163 | 1702 | 1566 | 2007 | 2069 |
Jul 18 | 2097 | 2078 | 2385 | 1922 | 1768 | 2228 | 2315 |
Jul 25 | 2334 | 2291 | 2601 | 2149 | 1988 | 2457 | 2568 |
Aug 1 | 2596 | 2548 | 2868 | 2401 | 2239 | 2716 | 2839 |
Aug 8 | 2809 | 2757 | 3104 | 2617 | 2438 | 2916 | 3071 |
Learn more about the newly developed
pear psylla management guidelines and phenology model
at WSU Extension.
Subscribe to DAS to get daily degree-days values, including
estimated forecasts, for any weather locations across Washington, Oregon and Idaho, together with
timed management guidelines and spray recommendations throughout the season.