Question
I've just moved into a new home this spring and the previous owner had a great dill garden growing by some fruit trees.  The dill was great until about a month ago...now its all bown and wilted.  Should I rip it all out and reseed in the spring or should I trim it back and let it grow back?  I live in st Louis where it's been very hot this summer.

Answer
Dill is an annual that does better in cooler weather.  Did it flower before turning brown?  Usually the heat will cause it to flower and set seed sooner.  
Did you notice any white on the leaves before it turned brown?  If so, then your dill probably had a fungus.
If there is any green on it you could try cutting it back. Otherwise I would rip it out.
If you replant by about mid to late August you should be able to harvest some leaves this fall - but probably not seeds. Otherwise you can wait and replant in the spring.