NDVI stands for Normalized Difference Vegetation Index It quantifies vegetation by measuring the difference between near-infrared (which vegetation strongly reflects) and red light (which vegetation absorbs) Chlorophyll and photosynthesis cause light absorption in the red region of the spectrum The healthier the plant is, the higher the index is. HOW TO READ THE MAP: The NDVI index is a value between -1 and 1. Anything below 0.2 has no vegetation. It can be water, snow, a road, bare soil, clouds, … The primary gradient of photosynthetic activity is from NDVI values from 0.2 to 0.9, and that is represented with a classic heat map from red to yellow to green. NDVI > 0.9 are colored magenta. Foliage generally does not have NDVI values this high. You should not see this color very often. It corresponds mostly to artifacts. The color legend is the same for all crop types, all soil types and all regions. WHAT IT MEANS IN AG: NDVI values obtained with satellite data with high temporal resolution have a strong correlation with crop phenological stages (emerged, maturity, harvest). However, there are certain limitations. For instance, during the early stages of crop growth, when the green leaf area is small, NDVI results are very sensitive to soil background effects. The NDVI may also saturate at later stages, when the crops reach canopy closure, and produce inaccurate results. Crop type, crop age, row width will have an impact on the color you see on the map. Your grower could have a field that shows up mostly as dark orange for a field with healty 1st year leaf trees. This also means the NDVI will vary throughout the season. Don’t forget the image comes from a satellite, not a fly by. Resolution of the images is not as good at what paid services like Ceres offer. Our product gives a general information of the health of a field. They will not be able to detect if a line is leaking or to analyse the health of a single tree. But it gives us a view of the rest of the field where we do not have a tension sensor. NDVI will let us know about the health of a crop. But as you know, ag is complex. A low NDVI does not mean it is caused by wrongful irrigation. Could be related to many other variables.