Attendees of a recent Cornell field day at the Musgrave Research Farm heard from a number of researchers on ways to manage nitrogen inputs and soil health through precision agriculture, writes Helen Margaret Griffiths on LancasterFarming.com.
Cornell professor of nutrient management Quirine Ketterings along with her post-doctoral associate Aristotelis Tagarakis, and a number of other researchers from across the state, have been working with GreenSeeker technology.
“GreenSeeker has been used in New York state for a number of seasons,” Tagarakis said.
The GreenSeeker scanner provides data known as Normalized Difference Vegetation Index, or NDVI, which is used to make decisions regarding the amount of fertilizer to be applied to a crop.
Tagarakis said there is still work to do to fine-tune the algorithms growers in New York state are using to convert NDVI values into nitrogen recommendations for corn. He said their data show that the sensor provides good predictions of yield when scanned at the V7-V8 growth stage for corn. For forage sorghum, taking readings at 30 inches plant height was a good time for predicting yield, he said.
Sarah Lyons, doctoral candidate with Ketterings, talked about why they were studying forage sorghum.
“Brachytic dwarf BMR sorghum is, as its name implies, shorter than the standard varieties and is branching, so there is less of an issue with lodging,” Lyons said.
Many believe it is a promising alternative to corn silage as it has good nutritional value and has the potential for earlier harvest, thus allowing for more flexibility in spring planting. Sorghum could fit into a rotation in upstate New York where harvesting the winter cereals in time for corn planting in the spring can sometimes be a challenge.
Lyons said the focus of some of the research has been the nitrogen needs of the crop and to determine the effect of harvest date on yield and quality.
“We’ve seen that harvesting two weeks earlier than normal doesn’t result in yield loss, but how the cows will do when they eat it is yet to be determined,” she said.
A much newer technology used in precision agriculture applications is aerial drones. Lindsay Chamberlain, a student at Cornell who works in Ketterings’ program and with drone expert Elson Shields, talked about some of the work they are doing with drones.