Trees can be classified as semi-antennas (semiconductor). If you have no
wire, tree is better than nothing (as radiator). But if you use a tree as an
antenna support, try to keep the wire away from the wood. It acts as a
capacitor - sucker of RF.
Once I put up Ground Plane antenna for 10 - 15 - 20 m (with elevated radials)
and I used varnished and well dried up bamboo as a support for #10 wires as a
vertical elements and taped the wires to the bamboo (nice insulator, right?).
Could not resonate the wires. When I put plexiglass spacers between the wire
and the bamboo - voilaaa. Resonance returned.
Another case of loosing RF by "suction" was when we used back in OK land 10 W
rig with kind of Inv L antenna with counterpoise. If we ran the antenna wire
close to the windowsill or wall, the RF was being "sucked" away. You could
see that by running the neon lamp by the wire before and after moving the
wire away from the objects.
So if you want to use the trees as support, try to use insulators and keep
the wire away or at close to 90 degree angle from the trees.
Wonder how good radiators are the petrified tress by Anchorage, AK (they
"drank" the salt water after the big earthquake)?
73 de Yuri oK3BU, VE3BMV
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