Issue 3, May 20, 2020

Modified Growing Degree Days (Base 50⁰ F, March 1 through May 18)

Station Location

Actual Total

Historical Average   (11 year)

One- Week Projection

Two-Week Projection

Freeport

209

327

283

367

St. Charles

234

313

302

379

DeKalb

219

361

299

389

Monmouth

315

411

398

491

Peoria

317

445

402

497

Champaign

339

449

430

531

Springfield

373

503

474

584

Perry

387

479

476

575

Brownstown

415

555

521

636

Belleville

521

583

629

748

Rend Lake

503

633

618

744

Carbondale

562

599

671

792

Dixon Springs

557

650

671

796

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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