Issue 1, April 28, 2014

Modified Growing Degree Days (Base 50°F,  March 1 through April 24)

Station Location

Actual Total

Historical Average (11 year)

One-Week Projection

Two-Week Projection

Freeport

134

117

175

235

St. Charles

103

118

140

197

DeKalb

97

134

140

206

Monmouth

119

163

167

237

Peoria

146

183

199

274

Champaign

167

183

220

295

Springfield

203

210

261

344

Brownstown

213

248

277

364

Belleville

240

266

306

395

Rend Lake

258

292

330

427

Carbondale

257

283

324

415

Dixon Springs

279

312

352

449

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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