nope. "Landscape Architect" is a protected legal title. In most states you need to meet education requirements and pass an exam to call yourself an LA. Landscape designer, you could decide working at Best Buy sucks, print up a bunch of cards that say landscape designer, and go into business.
In terms of the difference in the field, it depends. There's some overlap between landscape architecture and urban planning, and that LA stamp means you can do more with regards to grading and drainage, site planning, and wetlands. While I do some commercial work (I'm a landscape designer), I'm really selective about the projects I pursue because I honestly believe for many commercial jobs, LAs have a better set of skills via their training.
On residential (which is 80-90% of my practice), I'm often competing with LAs for design projects. Excluding jobs where an LA is required (wetlands, etc) I'd say who gets it comes down to portfolio, references, and salesmanship.
It all comes down to what you want to do with your degree. I think that unless you're one of the incredibly rare, talented exceptions, you learn design by studying or working under good designers. I think it's part of being an artist to look back on work you did ten years ago and be horrified at how bad it sucks compared to what you're doing now. Having the right instruction and guidance can shorten the time between suck and awesome though.