Issue 1, April 20, 2015

Modified Growing Degree Days (Base 50°F,  March 1 through April 15)

Station Location

Actual Total

Historical Average   (11 year)

One- Week Projection

Two-Week Projection

Freeport

108

76

140

177

St. Charles

110

78

141

175

DeKalb

106

89

141

180

Monmouth

144

111

183

228

Peoria

165

125

210

259

Champaign

168

126

212

261

Springfield

210

144

261

315

Brownstown

206

175

263

323

Belleville

246

189

306

368

Rend Lake

263

207

329

397

Carbondale

261

202

323

387

Dixon Springs

274

223

342

412

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). (Kelly Estes)

Author:
Kelly Estes

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