There is a book called The Secret Life of Plants, by Peter Tompkins and Christopher Bird, written in 1973. It is full of the most wonderful tidbits about plants and plant people. I've read it twice, once in the early 80's, and again a couple of years ago. I'm going to be referring to it as I write on this blog, and picking it up today to leaf through it, I see that I need to read it again.
Much of it could be dismissed by many as metaphysical nonsense; much of it wanders down paths of inquiry that have been forsaken by most researchers. But whether or not you groove on the "new-ageyness" of it, the mystical and magical, or you prefer your science hard, clear, and no nonsense, there are still many tantalizing researches and experiments that can't help but pique your interest no matter where you sit on the curve between whacko and stick-in-the-mud.
As I recall from reading it before, the authors begin each section by looking at the history of some aspect of plant life, whether it be from antiquity or from the early 20th century, then follow that aspect as it has been investigated up to the modern age. In most cases, the modern experimentation was ended by WWII, and there it's all sat since then. It struck me that many of these old inquiries are just waiting to be taken up again, a treasure trove of papers and theses and research projects for the 21st century.
Just to give an example, (I might have some of the details mixed up here, as I said I read this a few years ago, but if I find any significant errors when I come on it again, I will retell the tale correctly.) some researchers were interested in the possibly measurable responses of plants to their environment, so they hooked up some electronic devices to the leaves of some potted plants, and turned on their machines. They observed that when someone burned or cut the plant leaves, there would be one kind of response, which they interpreted as negative, and when the plants were kindly watered, cleaned, and cared for, there was a different response, which they of course termed positive. Then they found that the only stimulus needed to evoke either the positive or negative response was for the plant care person to simply think of either watering of cutting the plant. Then they saw that one particular person elicited the strongest positive responses when he came in to care for the plants. And then they found the coolest thing of all - they put some of the plants onto an airplane and sent them to the other side of the continent. And when the plants in the original site were watered and cared for, and they gave off the "positive" response, the plants 3000 miles away gave the same response at exactly the same time. Is that not amazing? And worth following up on, don't you think?