You don’t have to be a DIY expert or a chemistry whiz to try this trick. Here’s what you’ll need:

• Uncooked white rice
• Powdered plaster (  also called plaster of Paris or white cement  )
• Water
• Small containers (  bowls, bottle caps or small cocottes  )
• A blender or mortar

Grind raw rice into a fine powder. Mix it with chalk in equal parts. Pour this mixture into shallow containers near the pest areas.   Place   a small bowl of water next to each container;   this activates the trap  .