[Lowfer] Tree Experience

[JD]

>>> or is the relatively strong signal from the 50KW station also creating 
>>> some level of   "ionic"   non-linear conductivity process within in the 
>>> tree(s)---which then a portion thereof is re-radiated or otherwise 
>>> coupled to the e-probe?

A much simpler explanation may involve the height of the trees.

Although trees are highly resistive "antenna elements" by nature, they are 
still subject to resonance effects.  Their relatively large diameter and 
their inherent capacitive loading mean that most any full grown tree can 
have a substantially different amount of interaction with a 2040 kHz EM wave 
than it does at 1020 kHz.  Not only the height of their trees, but also the 
spacing, will directly affect the relative levels of carrier versus harmonic 
at any given point, since they can form a low-efficiency directional array 
of sorts.

I was able to witness this effect first-hand at an AM station a little over 
20 years ago, while trying to show the owners why they needed to deforest 
(no pun intended) the site to its early-1950s condition if they wanted the 
same coverage they had back when the station was new.

John