Cumulative number of diseased elms, alive elms, and percentage Dutch elm disease incidence since initiation of study in Detroit, Michigan, 1974-1978.
Treatment | 1974 | 1974-75 | 1974-76 | 1974-77 | 1974-78 | |||||
---|---|---|---|---|---|---|---|---|---|---|
DED | Alive | DED | Alive | DED | Alive | DED | Alive | DED | Alive | |
Girdlingplus prompt removal | 113 5.6% | 1923 | 184 9.1% | 1845 | 279 13.8% | 1743 | 358 17.7% | 1664 | 497 24.6% | 1525 |
Promptremoval only | 85 4.7% | 1735 | 155 8.6% | 1656 | 272 15.1% | 1532 | 377 20.9% | 1427 | 489 27.1% | 1315 |
Methoxychlorspray plus conventional | 116 6.4% | 1700 | 232 12.8% | 1579 | 430 23.8% | 1380 | 566 31.3% | 1244 | 714 39.4% | 1096 |
Conventional removal | 110 6.2% | 1659 | 208 11.8% | 1554 | 410 23.3% | 1352 | 556 31.5% | 1206 | 748 42.5% | 1014 |