---- Jason Hernandez <[email protected]> wrote: > The problem is that "people" (meaning laypersons from the point of view of > the particular scientific discipline) do not actually read *scientific* > literature on it. How often have we seen -- in books about horticulture, > landscape architecture, and so on -- that willows should not be planted near > underground pipes because their roots will enter and thus destroy said > pipes? To someone unfamiliar with the science behind it, it would *appear* > to be saying that the willows somehow detect the presence of water in the > pipes and grow into them seeking said water. Such literature does not make > explicit what we know: that this phenomenon presupposes that the pipes are > already leaking, the willow roots are already in contact with the resulting > gradient, and grow along the gradient into the existing leaks in the pipes. > Add to this the phobia of most non-scientists toward reading scientific > literature -- because they already assume they will not understand > it -- and there is little to counter such misconceptions arising from > oversimplification.
But any time we encounter such a misconception, we can correct it, if the person who holds it is willing and able to listen and understand. I have had various levels of success with such. For some, the response was simply that "that's how I understand it," meaning the incorrect way, with the implication being that they had no intention of understanding it differently. Some have seemed to think that an explanation of how something works is too much, that all they need to know is that (for example) roots end up where there is water, like in pipes, and who cares why for goodness sake. Others have listened, gotten a look of sudden understanding on their faces, and said that now it made sense. This is regarding a variety of things that folks might hold misconceptions about. But, I keep offering to explain, if anyone wants it. With some folks, it makes one seem unnecessary and intruding, so best to just leave it alone. mcneely Date: Thu, 26 May 2011 22:56:18 -0700 From: Wayne Tyson <[email protected]> Subject: Re: Plant roots matter Re: [ECOLOG-L] Communication Science to Public Plant Roots Dave, I don't know what "people" would say about the sealed container = exactly; I only know what many people, some who seem quite certain about = it, who apparently not only believe that roots search for water, but = think that water rises from the depths (all the way to the surface, far = above the capillary fringe, and who also apparently believe that water = from a single precipitation event, no matter how small, will eventually = reach the water table (capillary fringe, but I won't argue that). Most = people don't have any idea what a moisture gradient is, but are they = well- or ill-informed by science writing that implies or states outright = that roots can detect water and seek it out; that is, that roots can = grow through almost anything, no matter how dry, to "find" water?=20 WT Here's a story: Several years (decades) ago I heard a paper by a = "restoration ecologist" who was quite proud of spending well over = $200,000 ($218,000 as I recall) per acre to "create" riparian habitat = adjacent to a river in the southwestern USA. Many years later I was = asked by the responsible federal agency to assess why that "created" = riparian habitat was not working; why the trees (mature riparian trees = salvaged via "tree-spade") were not growing and were dying. The apparent = theory behind the "creation" project was that by cutting an adjacent = hill down to a level area adjacent to the river, tree-spading the trees = in, and watering them with a single drip emitter each, that the roots = would reach the water table and the trees would thrive. I had several = trenches dug to about 18 feet, sectioning a sampling of the trees in = question; the tree roots had not grown down through the intervening = formation to the water table because that formation did not contain = available water and there was no water table (except for one site, where = water was found, near the river, at about fifteen feet). The few roots = that could survive on the very little water from the drip emitter that = did not evaporate or was not transpired by weedy vegetation managed to = support about half of the leaf area of the tree-spaded trees. Adequate = irrigation would have provided a moisture gradient and adequate water = for growth or at least kept the trees alive, but they would have been = almost entirely dependent upon artificial irrigation forever. The = restoration ecologist had done no coring to confirm her theory that = there would be a water table adjacent to the river just like the = textbook says, but in many areas in the Southwest, rivers, especially = those with hillsides adjacent to their banks, are not textbook cases. = This fundamental error has been committed, I have been told, in other = places. There is no substitute for facts (determining feasibility), = especially when six- or seven-figure project costs are at stake. Any = such project should be based on what is actually feasible, not what is = desired, and an understand of plant-soil water relations is essential. = Yes, this is an anecdote. I have others, and they all answer to the same = fundamental principles.=20 -- David McNeely
