Issue 4, May 21, 2018

Modified Growing Degree Days (Base 50°F, March 1 through May 17)

Station Location

Actual Total

Historical Average (11 year)

One- Week Projection

Two-Week Projection

Freeport

319

307

391

471

St. Charles

332

295

399

473

DeKalb

295

339

374

461

Monmouth

404

387

488

576

Peoria

426

421

511

601

Champaign

460

424

550

648

Springfield

560

475

661

767

Perry

568

454

657

752

Brownstown

540

528

644

756

Belleville

573

555

681

796

Rend Lake

616

603

730

852

Carbondale

575

571

681

798

Dixon Springs

642

621

754

875

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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