It is real easy to do. Since you mention Bermuda and SA I can assume you live in warm season grass territory so I would eliminate the Fescue.

As for either Bermuda or SA depends on your shade issues. If you have a shady lawn then SA would be the choice. If sunny then Bermuda but it comes with high maintenance of mowing 2 or 3 times a week, and fertilizing 5 to 6 times per season.

OK to eliminate the Fescue, just spray the lawn with Atrazene one time and it is gone. To eliminate the Bermuda apply several applications of Atrazene spread out over a several weeks, then periodically during the growing seasons to keep control of the Bermuda.

Too get rid of the SA spray with a product containing 2,4-D or 2,4-D and dicamba, or MSMA. Make sure 2,4-D is the top ingredient if you use these mixtures. (Timec Plus)

Thanks for the tips, texas-weed. Given our south-facing, nothing-but-sun front yard, I think Bermuda is the answer. I'm not super excited about the mowing practices, though.

I've read your Bermuda Bible (thank you), which says that common varieties can be mowed to between 1-1/2 and 2 inches. At those heights, will the same 2-3 times per week frequency be required? What results from less mowing? Seed heads? Thinning?

I don't mind the fertilization schedule. I'll be going the organic route, so I'm thinking soybean meal, CGM, or alfalfa pellets once per month. Any opinions about which one of those will be best for Bermuda?

Also, given my organic care leanings, will general good Bermuda practices eventually crowd out the fescue?

Bermuda Bible, which says that common varieties can be mowed to between 1-1/2 and 2 inches. At those heights, will the same 2-3 times per week frequency be required?

No.

The rule of thumb for mowing any grass type is to never remove than 1/3 blade length. Many if not most of the Bermuda hybrids and even some of the improved common varieties can be maintained at 1/2 and less with some of the dwarf varieties. If kept that short requires mowing every other day. Bermuda grass very fast, so fast under the right conditions you can dang near see and hear it grow. When kept at say 1.5 inches you would be looking to mow every 5 to 7 days, and under some conditions, wet and warm, every 3 to 4 days.

What results from less mowing? Seed heads? Thinning?

Correct.

Bermuda has a unique characteristic in that it can be trained to do something no other grass can do. Some expert says it is self defense. When kept short and mowed frequently the blades learn to lay low and grow horizontally to avoid the blade. When this happens the grass interweaves into a tight dense mat of carpet. It forms a barrier weeds have difficulty breaching.

As the maintenance height is raised allows the grass to grow more vertically, which loosens up the density and opens the canopy so to speak. It begins to thin out which opens up more opportunities for weeds to invade.

I don't mind the fertilization schedule. I'll be going the organic route, so I'm thinking soybean meal, CGM, or alfalfa pellets once per month. Any opinions about which one of those will be best for Bermuda?

Also, given my organic care leanings, will general good Bermuda practices eventually crowd out the fescue?

If you are going to go the organic route for economic-technical reasons I would suggest Milorganite over the feed-grains. Of the three you listed Soy Bean Meal would be #1 choice. CGM is great but very expensive and SBM has about the same protein content. Alfalfa pellets are uselees on Bermuda, as is corn meal.

FYI Bermuda is a nitrogen hog, and many if not most of the organic alternatives cannot supply enough nitrogen fast enough to meet the demand early on and may take a season or two to build up the soil microbes to digest the food grains. However Milorganite works pretty much just like commercial fertilizers. IT has slow release nitrogen but not painfully slow and has some iron in it which is welcomed in any lawn.

Now with all that said consider this. For the first season to kick start the Bermuda growing use a commercial slow release urea fertilizer for the next 2 months. Then 1 half application commercial urea, and half organic choice.

You don't really have to mow that often, only if it rains a lot or you water a lot. You can go 2 weeks and still have a decent lawn. IMO, not worth the trouble to maintaining perfect golf condition with that much mowing at low cutting height. Just have to make sure to apply pre-em weed control at the right time and provide enough nitrogen to get at least a decent looking lawn with minimal work.