What time does the park open? And is there a trail map for bikes?

Yes there's a map showing trails and the entire area. And they're dawn to dusk as most places like this are.

Thanks for your interest. District lands are free and open to the public from sunrise to sunset. Links below to some information you may find useful. Using district lands: www.sjrwmd.com/lands/recreation/usinglands Property info: www.sjrwmd.com/lands/recreation/hal-scott Trail guide: www.sjrwmd.com/static/lands/trailguides/halscotttrail.pdf