Add just enough fertilizer, and crops thrive. Add too much, and you may end up with contaminated surface and groundwater.
It can also fluctuate depending on soil type and even if organic additions, like manure, are applied.
Ali is lead author of a new study that shows water infiltrates deeper into cracking clay (vertisolic soils) when liquid hog manure is applied.
The study also showed that even though water infiltration went deeper in the presence of manure, it did not reach depths of 39 inches (100 cm). That’s how deep tile drains—designed to remove excess subsurface water—are typically installed in the study region.
Read more at American Society of Agronomy
Image: At the onset of the experiment, a pesticide sprayer is used to apply blue-dyed water on top of a 39 inch square (1 m by 1 m) soil plot. (Credit: Genevieve Ali)