In Sarnia, the 3rd generation of cabbage maggot are expected to emerge in next day or so. In the London area, accumulated degree days have reached the threshold indicating the emergence of the 3rd generation of cabbage maggot. Also, in the London area, expect the 3rd generation of onion maggot to emerge in about 3-4 days.
Here are the degree days accumulated from April 1st until August 15th, 2011.
| Area |
Onion Maggot(base 4) |
Cabbage Maggot(base 6) |
Carrot Rust Fly (base 3) |
Carrot Weevil (base 7) |
| Bradford/Holland Marsh* |
1676.5 |
N/A |
1808.3 |
N/A |
| Sarnia |
1678.6 |
1435.8 |
1807.2 |
1320.6 |
| London |
1723.8 |
1474.7 |
1852.9 |
1353.4 |
| Wellington |
1499.5 |
1257.4 |
1624.3 |
1139.5 |
| Windsor |
1969.5 |
1710 |
2103.5 |
1587.6 |
| Area |
Tarnished Plant Bug (base 12) |
Leafhopper (base 9) |
GDD (base 5) |
| Bradford/Holland Marsh* |
764.6 |
1075.5 |
1548.2 |
| Sarnia |
793.8 |
1098.6 |
1555.1 |
| London |
798.9 |
1119.9 |
1598 |
| Wellington |
620.7 |
917.1 |
1377.2 |
| Windsor |
1022.6 |
1352.5 |
1837.2 |
* Data provided thanks to Muck Crops Research Station, Department of Plant Agriculture, University of Guelph
Degree day information for pests
|
|
Degree Days |
||
|
1st Generation |
2nd Generation |
3rd Generation |
|
| Onion Maggot |
210 |
1025 |
1772 |
| Cabbage Maggot |
314-398 |
847-960 |
1446-1604 |
| Carrot Rust Fly |
329 – 395 |
1399-1711 |
n/a |
| Carrot Weevil |
138 – 156 |
No model available |
n/a |
| Tarnished Plant Bug |
40 |
n/a |
n/a |
| Aster Leafhopper |
128 (overwintering egg hatch) 390 (local adult emergence) |
n/a |
n/a |
