Normalised Difference Vegetation Index (NDVI) and Crop Sensors

Precision Ag – Leighton Wilksch talks about Normalized Difference Vegetation Index (NDVI), and Sam Trengove talks about crop sensors.

Normal Difference Vegetative Index

In NDVI stand for Normal Difference Vegetative index that is a standard factor of crop growth that is utilised world wide there is a number of variation on a theme but it basically uses the reflectance of a crop of the red and near inferred light and the algorhythm is created  to create a number between Naught and one that we can use to identify the greenness and the bulk and the biomass of the crop.

NDVI and usually collected through the use of satellite, remote sensing, you might see it in the air airplane flying with specific expensive cameras that can do the job but there is also a different range of crop sensors That can pick up the reflectance from the crop, they are to have their own light source or they utilize the light that is here during the day.

With those sensors we can. Create a map of crop growth and the bulk and the bimass from there we can go on and use that information to make some decisions about How the crop is growing, B why the crop is growing poorly in one area and better in another and then C formalte a plan on what we are going to do with that which is typically is a variable right application rate plan for nutrition.

The Main Focus of Crop Sensors

The main focus with these sensors is looking at targeting nitrogen applications and looking at variable rate nitrogen applications. It’s around the time that you want to be out there, putting in, on the crop. Typically it’ll be around that five leaf through to mid stem elongation period that you’ll get the best indication from them in terms of the variability in the crop.

If you go very early on in the crops growth, and it’s nitrogen demand has been very low, and so the variability that exists in the crop will be minimal and not caused by nitrogen. You can just have these sensors set up on either your boom spray, or your spreader and be mapping each time you pass over the paddock back to your home office and interrogate the maps, see what they have are showing you, then you can tweak those and send them back out to a variable rate controller and do your variable rate application then.

If you’re comfortable with the sensors picking up variability that is associated with nitrogen availability you can set the senses up to control all of your spreader or your boom spray with UAN on the go in real time. As it senses it controls an algorhythm which gives you an N rate and then that controls the actual output on the go.

Usually what we are seeing is not so much a reduction in the cost of the input . So a farmer not so much looking Cut rights, but we’re just looking at a redistribution of rates of nutrition. We actually can utilise the NDVI. We can redistribution the nitrogen over those areas and essentially get a better bang for our buck.