Issue 2, May 5, 2020

Modified Growing Degree Days (Base 50⁰ F, March 1 through April 4)

Station Location

Actual Total

Historical Average   (11 year)

One- Week Projection

Two-Week Projection

Freeport

136

190

202

272

St. Charles

154

185

218

283

DeKalb

140

212

212

289

Monmouth

224

248

302

387

Peoria

226

275

309

395

Champaign

242

275

326

415

Springfield

276

311

369

468

Perry

293

304

377

467

Brownstown

311

358

407

509

Belleville

389

378

489

595

Rend Lake

373

414

481

592

Carbondale

406

398

505

608

Dixon Springs

420

436

526

635

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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