Evaluation of a Reduced Cost Active NDVI Sensor for Crop Nutrient Management

Table 6

Pocket sensor NDVI values based on 95% confidence levels for turf grass, wheat, and maize canopies.

Sensor	Crop	Type estimate	Pred. NDVI	Range NDVI	Pred. NDVI	Range NDVI	Pred. NDVI	Range NDVI	Pred. NDVI	Range NDVI	Pred. NDVI	Range NDVI	Mean NDVI by sensor
			0.4		0.5		0.6		0.7		0.8
19	Grass	Average	0.388		0.497		0.605		0.713		0.821
19	Grass	95% extreme	0.372	0.016	0.479	0.018	0.585	0.020	0.691	0.022	0.797	0.023	0.020
20	Grass	Average	0.402		0.505		0.607		0.710		0.812
20	Grass	95% extreme	0.388	0.014	0.489	0.016	0.589	0.018	0.690	0.019	0.791	0.021	0.018
27	Grass	Average	0.401		0.508		0.614		0.721		0.828
27	Grass	95% extreme	0.386	0.015	0.491	0.017	0.596	0.018	0.701	0.020	0.807	0.022	0.018
32	Grass	Average	0.398		0.499		0.599		0.700		0.800
32	Grass	95% extreme	0.382	0.016	0.481	0.018	0.580	0.019	0.679	0.021	0.777	0.023	0.019
37	Grass	Average	0.403		0.507		0.610		0.713		0.816
37	Grass	95% extreme	0.388	0.016	0.489	0.018	0.590	0.019	0.692	0.021	0.793	0.023	0.019
27	Maize	Average	0.403		0.507		0.611		0.716		0.820
27	Maize	95% extreme	0.348	0.054	0.446	0.061	0.544	0.068	0.642	0.074	0.739	0.081	0.068
37	Maize	Average	0.408		0.508		0.607		0.707		0.806
37	Maize	95% extreme	0.378	0.030	0.474	0.034	0.570	0.037	0.666	0.041	0.762	0.044	0.037
20	Wheat	Average	0.418		0.517		0.616		0.716		0.815
20	Wheat	95% extreme	0.369	0.049	0.464	0.053	0.559	0.057	0.654	0.062	0.749	0.066	0.057
32	Wheat	Average	0.403		0.502		0.601		0.700		0.798
32	Wheat	95% extreme	0.346	0.057	0.440	0.062	0.534	0.067	0.628	0.071	0.723	0.076	0.067

Pred. NDVI: predicted NDVI based on pocket sensor reading.
Range NDVI: NDVI difference from average predicted value.
Type estimate: average: average value based on pocket sensor calibration.
95% extreme: the most extreme value displayed by the pocket sensor with 95% confidence limit.