Issue 3, May 20, 2019

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

Station Location

Actual Total

Historical Average   (11 year)

One- Week Projection

Two-Week Projection

Freeport

227

297

299

377

St. Charles

218

285

284

357

DeKalb

207

328

285

370

Monmouth

287

375

371

458

Peoria

328

409

413

502

Champaign

385

411

475

570

Springfield

415

461

515

619

Perry

416

441

506

599

Brownstown

446

514

549

659

Belleville

537

540

644

757

Rend Lake

549

588

662

782

Carbondale

556

557

661

776

Dixon Springs

589

605

701

820

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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