If you have not already been to it already. I suggest you check out Redbud Valley Nature Preserve. They are are open daily, except for most city holidays, from 8:00 a.m. - 5:00 p.m. At Oxley, you may park outside the gates from 7:00 a.m. - 9:00 p.m. to walk the trails even when the gates are closed.
The Oxley-Yetter Interpretive Building is open daily, except for city holidays, from 10:00 a.m. to 4:30 p.m. Mondays through Saturdays, and Noon to 4:30 p.m. on Sunday.

http://www.oxleynaturecenter.org/redbud.htm