Mid-Season Determination of Quality Parameters in Silage Corn Using the Greenseeker Sensor.

Laboratory procedures are traditionally applied to determine various quality parameters of corn silage. Even though effective in determining forage quality, this analysis is conducted post-harvest and does not allow for management adjustments in the standing crop when quality standards are not met.  Predicting quality factors mid-season would help producers to make management adjustments in the growing crop. The objective of this study is to investigate if mid-season reflectance measurements could be used to predict crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) in silage corn. Two corn hybrids will be evaluated in a field experiment at the Mann Valley Farm in River Falls, WI. Pre-plant nitrogen (N) was applied at 120 pounds per acre while, selected treatments will get additional N at 20, 40, and 60 pounds per acre. The GreenSeeker will be used to collect normalized difference vegetation index (NDVI) readings at V4, V6, V8, V10, and V12 growth stages. Correlation and regression will be used to evaluate the relationship between NDVI and biomass, CP, NDF, and ADF. Results will show that late season NDVI readings are highly correlated with crude protein and could aid in making adjustments when target quality values are not met.