Assessing the Spectral Separability of Flue Cured Tobacco Varieties Established on Different Planting Dates and under Varying Fertilizer Management Levels

Table 7

Optimum times for discriminating crops for different planting times.

Weeks from September 1	Spectrally dominant crop	Crop area (A)
0–9	September (s)	𝐴=𝐴s only
10–12	September (s) + October (o)	𝐴=𝐴s+𝐴o (𝐴s > 𝐴o)
13–15	September (s), October (o), and November (n)	𝐴=𝐴s+𝐴o+𝐴n; NDVIo > NDVIs > NDVIn
16–18	October (o) and November (n)	𝐴=𝐴o+𝐴n; NDVIo ≥ NDVIn
18–20	October (o), November (n), and December (d)	𝐴=𝐴o+𝐴n+𝐴d; (NDVIo = NDVIn) ≥ NDVId
20–22	November (n) and December (d)	𝐴=𝐴o+𝐴n+𝐴d; NDVIo = NDVIn = NDVId
23–26	December (d)	𝐴=𝐴d; NDVId only

One has the following:
(1) 𝐴: crop area,
(2) 𝐴_s, 𝐴_o, 𝐴_n, and 𝐴_d: areas for the September, October, November, and December crops,
(3) NDVI_s, NDVI_o, NDVI_n, and NDVI_d: NDVI for the September, October, November, and December crops.