Issue 5, June 29, 2023

Modified Growing Degree Days

Modified Growing Degree Days (Base 50⁰ F, March 1 through June 27)
Station Location Actual Total Historical Average   (11 year) One- Week Projection
Freeport 1070 995 1214
St. Charles 1051 965 1199
DeKalb 1051 988 1197
Monmouth 1276 1157 1438
Peoria 1251 1208 1420
Champaign 1356 1262 1522
Springfield 1345 1398 1522
Perry 1325 1317 1498
Brownstown 1559 1304 1741
Belleville 1460 1494 1652
Rend Lake 1574 1593 1775
Carbondale 1465 1518 1665
Dixon Springs 1497 1546 1692

Insect development is temperature dependent. We can use degree days to help predict insect emergence and activity. Home, Yard, and Garden readers can use the links below with the degree day accumulations above to determine what insect pests could be active in their area.

GDD of Landscape Pests
GDD of Conifer Pests

Degree day accumulations calculated using the Pest Degree-Day Calculator Calculator (a project by the Department of Crop Sciences at the University of Illinois and the Illinois Water Survey).

Author:
Kelly Estes

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