We do not usually feel electrical forces because we and the objects around us are usually neutral.
Charged materials attracting uncharged materials produces static cling.
This charge assignment would really have to be experimentally verified using an electroscope. This is similar to the previous question. The conducting tires prevent charge buildup on the truck, thus reducing the possibility of an electric spark discharge that might ignite flammable cargo. The mobile charge distributes itself over the outside surface of the metal stem and leaves. Because the leaves have the same sign charge they mutually repel and separate.