Imagine, or just push the fast-forward button: You activate your sensor network to take soil, root and leaf readings and report data. You receive temperature, moisture, plant hormone levels and more from georeferenced points. Your computer integrates them with already-identified and mapped organic matter (OM), pH and electrical conductivity (EC) zones in those fields, with the specific variety planted.

You output an application map with recommended rates varied by zones for selected herbicides. Download the map to the crop-reflectance-camera-equipped applicator for more refinement on the go. As it crosses the same field, ratio and volume vary according to crop and weed biomass levels and reflectance values. The end result is maximum weed control, minimal crop impact and least-cost application.

Much of this data is already available. Some of the sensors and the network to power and operate them are still under development. Some are still being envisioned by ag researchers studying the fast-changing world of field and crop sensor technologies.

Other scenarios include in-crop sensing of available nitrate forms and conditions such as temperature and soil moisture likely to impact near-term conversion, as well as uptake. Adjusting application rates accordingly would offer maximum yield at least cost per additional unit of input.

"The goal is a complete picture of what's happening in the field," says Chad Fick, OptRx product specialist, Ag Leader Technology. "Right now optical sensors can ask a plant if it is healthy or not relative to nitrogen utilization. However, this is a more complex question than simply N, and this is where the technology is going, not just to the major elements, but to a bigger picture of what is happening in the field to help growers make decisions based on what's available to them at the time."