Issue 4, June 1, 2020

Modified Growing Degree Days (Base 50⁰ F, March 1 through May 31)

Station Location

Actual Total

Historical Average   (11 year)

One- Week Projection

Two-Week Projection

Freeport

405

472

503

631

St. Charles

444

447

534

654

DeKalb

430

517

533

666

Monmouth

535

572

643

780

Peoria

538

610

650

790

Champaign

576

626

694

841

Springfield

619

697

742

894

Perry

612

652

725

866

Brownstown

646

759

775

931

Belleville

779

793

908

1054

Rend Lake

753

855

892

1055

Carbondale

833

810

966

1119

Dixon Springs

809

870

946

1103

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 Illinois IPM Degree-Day 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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