Nitrogen Response Following Nitrogen Response Following CornCorn

N rate (lb/acre)0 50 100 150 200 250 300

Yiel

d (b

u/ac

re)

100

120

140

160

180

200

220

240

260

BellwoodCairoClay Center 1North PlattePaxton

Spider mites, irrigation uniformity??

???

2002 was a high-yielding year. Maximum yields 2002 was a high-yielding year. Maximum yields ranged from 210-259 bu/acre at 8 sites. ranged from 210-259 bu/acre at 8 sites.

Corn after soybean: Corn after soybean: variation in 0-N yield, but similar optimal N variation in 0-N yield, but similar optimal N

rate at all sites (120-130 lb/acre)rate at all sites (120-130 lb/acre) UNL recommendation always the most UNL recommendation always the most

profitable treatment.profitable treatment.Continuous corn: Continuous corn:

varying N response, yield often increasing varying N response, yield often increasing with N rate up to 300 lb/acre, but at the cost with N rate up to 300 lb/acre, but at the cost of decreasing NUE.of decreasing NUE.

UNL recommendation was not always the UNL recommendation was not always the most profitable treatment.most profitable treatment.

First Year ObservationsFirst Year Observations

IFAFS – Thematic Soil Mapping ProjectIFAFS – Thematic Soil Mapping Project