You will not automatically be appointed an attorney. Appointment of the public defender should be viewed as a last resort for people who have absolutely no funds or assets with which to secure counsel.
As for the need for an attorney, it is always advisable to have an attorney when you're charged with a crime. Your attorney will watch out for hidden loopholes in prosecution and make sure that you fully understand what is going on at all times.
Not only is it not automatic, if no one is seeking jail time on you, it simply is not going to happen at all.
Before thinking woo hoo, no jail time and busting out happy feet, keep in mind that a conviction is a public record, and comes with court costs, fines, sometimes community service, and other potential hoops and hurdles.
While having counsel isn't an iron clad ticket to a dismissal and an apology, you really won't have a shot at a dismissal on your own, nor is a layperson likely to be able to minimize the hoops and hurdles the prosecution may want to drape all over you..
In sort, carefully consider the bigger picture of what not having counsel may mean for you.
It is always advisable to speak with counsel in these situations like the other attorneys have suggested.
As for if you technically need an attorney or not depends on the jurisdiction. Here in Cleveland County the judges require attorneys for Larceny charges since they could be enhanced to felonies after a number of subsequent offenses. Speak with competent counsel (not someone trolling the hallways) or make an application for public defender.