Issue 5, May 26, 2015

Modified Growing Degree Days (Base 50°F, March 1 through May 21)

Station Location

Actual Total

Historical Avg.   (11 year)

One- Week Projection

Two-Week Projection

Freeport

408

348

484

571

St. Charles

414

333

484

564

DeKalb

413

384

496

588

Monmouth

519

435

603

700

Peoria

545

470

631

730

Champaign

579

476

672

777

Springfield

665

533

767

880

Brownstown

626

587

733

852

Belleville

712

616

823

944

Rend Lake

782

668

899

1028

Carbondale

727

632

838

962

Dixon Springs

745

684

862

989

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). (Kelly Estes)

Author:
Kelly Estes

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