Applebee's employee harassment Lodi California

If I were you I would quit while you can still get a good reference from this company. It is not against the law for a company to have a dress code or a rule about grooming and long hair. You are expendable and you won't accomplish anything by going above your immediate manager's head. Frankly, his "kicking the shins" carries alot more weight than the hair issue and is the bigger grievance. It is very hard to enforce employment law and a discrimination case in the valley--it has to be a very blatent grievance and violation of the law. Don't count on help from the labor board. What the previous commentator said about management and servers being expendable is correct.

If you do go above this manager's head, get your resume ready and have your ducks all in a row...don't expect to have the job much longer after that.

Be very careful about how you talk to a district manager. You stated your age and unfortunatly that will be held against you.
Document everything! Take a notpad and take notes on time place,etc.. This is for your protection. After this you will be able to state to this persons boss exactly the when and wheres. If asked what you are doing be honest, and if need be file a complaint with your states labor board and the EEOC. Most of these complaints will be handled at a district level, but if you have to go to corporate. This guy isn't signing his own paycheck!
Don't be dismayed if they blow you off. Servers are considered expendable and not worthy of the time and energy of management.
Stay calm, yelling, cursing, screaming only cause people to ignore you. Think about how you react when someone yells at you and do the opposite. That fact that he is hispanic means nothing, being a jerk doesn't belong to any nationality. So DO NOT bring it up. You will look childish and bigoted.
Read your companies policy on what is considered appropriate hair length for ALL servers. If there is a state or city code for servers research that also. Remeber knowledge is power.
You didn't state if you were the one being hit or not, but if this supervisor does assault you again call the POLICE! Make them file a report, and follow through with it!
Best of luck!