Issue 4, May 18, 2015

Modified Growing Degree Days (Base 50°F,¬† March 1 through May 14)

Station Location

Actual Total

Historical Average   (11 year)

One- Week Projection

Two-Week Projection

Freeport

331

277

402

478

St. Charles

325

267

391

461

DeKalb

328

307

405

488

Monmouth

437

351

521

606

Peoria

457

384

543

629

Champaign

481

386

571

664

Springfield

565

433

665

767

Brownstown

530

485

632

739

Belleville

604

510

710

821

Rend Lake

662

556

773

891

Carbondale

618

528

722

833

Dixon Springs

641

575

751

867

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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