Thanks for taking the time to write up such a great answer Ent! Exactly what I hoped to see, so we all can have a somewhat more informed idea about it all. It easily becomes "Some people think this, but others disagree" otherwise if you are not knowledgeable on the subject.entropyembrace wrote:Plant roots selectively uptake nutrients from the soil. Other than a few exceptions chemicals can only enter the roots of plants if the plant is producing transport proteins specifically to acquire that substance from the soil. Since camphor is not a nutrient which plants use (it's a toxin a few closely related plants produce for protection) I find it extremely unlikely that tea trees would acquire camphor from the soil.bliss wrote: What about millenniums of camphor leaves, branches and trunks molting down into soil? Such a soil would definitely be unique in some ways. Just a thought that struck me when I was thinking about this. I know very little about how the extraction of minerals and other goodies (oils??) from soil via roots actually works.
Also, soil bacteria have enzymes to degrade camphor, so all those millennia of camphor trees being degraded in the soil? the camphor is being degraded by bacteria too. Some of them even use it as a carbon source (food).
The comparison with iodide isn't valid. Iodide is a simple ion which is a micronutrient required by most forms of life. The plants are taking iodide from the soil because they need it too, not because they're randomly taking everything from the soil.
Now is probably a good time to return back on topic. If anyone has counter-arguments, a new thread should be created.