Issue 3, May 19, 2021

Modified Growing Degree Days (Base 50⁰ F, March 1 through May 16)

Station Location Actual Total Historical Average (11 year) One-Week Projection
Freeport 293 214 412
St. Charles 313 211 436
DeKalb 301 212 421
Monmouth 351 303 475
Peoria 368 331 492
Champaign 389 358 516
Springfield 413 432 548
Perry 435 406 564
Brownstown 431 417 561
Belleville 482 509 614
Rend Lake 544 562 678
Carbondale 534 535 666
Dixon Springs 557 563 690

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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