It seems Dr.Michael Knoblauch at Washington State University is a very determined person. He is trying to prove a longstanding hypothesis about how nutrients are transported in plants.
Back in 1930 German plant physiologist, Ernst Münch came up with the hypothesis that nutrients should flow from areas with higher pressure (the leaves, where sugars are added to the system) to areas with lower pressure. As Dr. Knoblauch says, the Münch hypothesis “is super simple and super plausible”, “But it’s untested.”
You can check out where it now stands in the article entitled “Exploring a Tree One Cell at a Time” by Henry Fountain at the New York Times.