Issue 3, May 13, 2013

Modified Growing Degree Days (Base 50° F,  March 1 through May 9)

Station Location

Actual Temperature

Historical Average   (11 year)

One- Week Projection

Two-Week Projection

Freeport

192

228

261

333

St. Charles

207

221

272

338

DeKalb

204

254

278

356

Monmouth

237

292

320

404

Peoria

256

322

343

428

Champaign

285

323

373

463

Springfield

292

364

390

490

Brownstown

326

413

427

530

Belleville

340

435

445

552

Rend Lake

386

476

497

610

Carbondale

371

455

473

578

Dixon Springs

388

497

497

608

Insect development is temperature dependent. We can use degree days to help predict insect emergence and activity.  In warm years, insects emerge earlier, like we experienced last spring. Degree day accumulations are slightly behind the 11-year average. 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 University of Illinois Department of Crop Sciences and the Illinois Water Survey). (Kelly Estes)

Author:
Kelly Estes

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