Check out old knob and tube wiring

Also, wood is not generally regarded as a conductor of electricity. We make electrical wires out of copper, and sometimes aluminum for lower voltage stuff.

Also, by no means do I claim that large trees block all Electro-magnetic pollution. I'm only claiming that it mitigates it and does block some of it and transform it into thermal radiation.

I did more research and read that there is actually a paint you can by that is supposed to block wifi signals and cellphone signals and such. Also, I read that screening acts as a sort of faraday cage. So you can put screens on all your windows to block the government satellite from trying to beam in rays into your bedroom into your head.