Yes.
water and scrubbing with a rag.
Pine tar is very sticky and allows the batter to get a better grip of the bat when they use it on their batting gloves.
Dodgers righthander Jay Howell was ejected from Game 3 of the 1988 NLCS, against the Mets, when pine tar was found in his glove. Lefthander Kenny Rogers of the Detroit Tigers was accused of using pine tar during the 2006 World Series.
Its not that they put pine tar on their helmets on purpose. Its from handling the bat with their gloves, then both adjusting/taking off their helmet. So it just transfers from bat to helmet via the glove. Sure they could clean their helmets after a game, but I'm sure its a superstitious thing with many baseball players to not clean the helmet. I'm sure you've seen tons of ball players with extremely dirty helmets... Also... ball players ''adjust'' the amount of pine tar on their gloves for preference by touching their helmet to take some of it off.
No. It will get moldy when the pine tar oozes out. Keep them dry.
pine tar come from a pine tree
The best way is to spray it on with a spray jar. Put the pine star substance in a spraying container and spray it on, the more you spray, the thicker it will be. You can also get a, what people like to call, a Pine Rag, which is a rag that is covered in pine tar, then wiped on the bat. Remember! The more pine tar you add, the thicker it will be!
No. Pine-tar is a grip. Glue will stick. Unless you wanted your hand to not come off the bat...
Yes!
pine tar
You want a very light layer on the handle. It is wise to put a more hefty layer either on your helmet or on the top (barrel end) of the handle to use when the pine tar already on the bat wears off. Most pine tar is either in a stick that you rub on like chap stick, or in liquid form on a rag, which you rub on as well.
Pine tar is applied to the bat for a better grip, not the helmet. The reason why you see pine tar on some player's helmets is because it is transfered from the bat onto the players hands and then the helmet when they take off or adjust the helmet.