
For most of these examples a wand would not be necessary. The purpose of a wand in magic is usually as a director of energies. A wand tapers to a point and is favoured by many witches as bringing a precision to the energy they wish to control. A wand can be used to draw the boundaries of a circle for those witches who practise circle work where the energy is focused to separate a small area from the mundane world to be used for magical workings. Similarly some witches use a wand to create a circle for protective purposes, raising a boundary that negative energies cannot cross.
A wand can be a useful tool but is by no means a requirement and many witches choose not to use one.
Image http://www.deviantart.com/art/Pentacle-oak-wand-55111498