Issue 4, June 1, 2021

Modified Growing Degree Days (Base 50⁰ F, March 1 through June 1)

Station Location Actual Total Historical Average (11 year) One-Week Projection
Freeport 534 463 682
St. Charles 553 452 704
DeKalb 537 463 686
Monmouth 603 579 742
Peoria 635 615 776
Champaign 676 655 813
Springfield 708 749 850
Perry 707 698 846
Brownstown 753 694 892
Belleville 778 830 917
Rend Lake 851 902 988
Carbondale 825 857 960
Dixon Springs 847 890 981

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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