I recall comments at a hamfest talk several years ago from Roy, W7EL, that
his two-element 40m vertical array appeared to have an unintended null in
the direction of a stand of evergreen trees not too far away from his
antenna system. While this is two octaves above 160m, it at least
indicates the possibility of absorption problems. In all likelihood,
different tree species at different times of year could introduce a lot of
variability.
That was a rather dense stand of trees.
A few trees a reasonable distance from a LF antenna are not going to do
anything observable. A single tree at 2 GHz can mean 20-40 dB. It has
nothing to do with resonance, but rather how much the electric field is
killed by the resistors sticking up in the air.
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Stew Perry Topband Distance Challenge coming on December 29th.
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