Yarrow is a great "weed". If you crush the leaves, it smells like Bactine (remember that!). Works as an antiseptic on cuts, etc. But soaked in vodka or everclear for one month it makes a great organic insect/mosquito repellent. Stuff a mason jar full of crushed yarrow leaves. Fill the jar up with vodka or Everclear. Put the lid on and soak for a month. Strain the leaves out, put it in a spray bottle.Definitely keeps the mosquitos away. If you use Everclear (pure grain alcohol), and mix that 3 parts aloe vera gel to 7 parts of the everclear makes great hand sanitizer that repels mosquitos. You can't use vodka to make hand sanitizer as it is only 70% alcohol. By the way, don't drink the mosquitos repellent!!!!!!