| When you say you "put down" Bermuda, do you mean sod or seed? I believe only "common Bermuda" is available as a seed... at least that was the case twenty years ago. Common Bermuda isn't very attractive. Zoysia is superior in that it is thicker and more shade tolerant. Your Bermuda bare spots could be due to shade, or areas where seed didn't take. If, however, sod died in one season in sunny areas....then you didn't water enough during establishment or burned it with fert or weed killers. Fungus can kill Bermuda forming nearly perfectly round dead spots. Fungus is more likely in thick lawns. It might be better to kill the Bermuda with Round-Up before taking a sod cutter to it. I'm not sure if you need to remove the dead Bermuda before sodding zoysia. I suppose that depends on specific lawn conditions. A properly installed zoysia sod wont have too many problems with Bermuda invading it because of zoysia's thickness. But remnants of your Bermuda will probably pop up in sunny flower beds. Bermuda and Zoysia should get a pre-emergent in the spring to prevent crabgrass and in the fall to prevent annual blue grass. But an established, thick, zoysia lawn may be able to do without weed control chemicals. Zoysia does best if mowed with a "reel mower" and should be mowed fairly low. "Emerald" zoysia is mowed even lower than "Myers". But grass mowed low really reveals the imperfections (bumps and depressions) in your turf. So a little work every spring filling in low spots with a dirt/sand mixture makes a huge difference in sod lawn. The billiard table look can be achieved over time. I have seen lawns where zoysia was plugged into the bare shady spots to take over and Bermuda was left in the sunny spots. It works ok but isn't as attractive as a pure zoysia lawn. St. Augustine is even better for shady lawns. Core aeration definatly helps and should be done in the early spring just before the pre-emergent is applied. (Aerating weakens a pre-emergent and invites weed seed germination). If your lawn is heavy clay, shortly after aerating, there is an opportunity to spread soil amendments (such as sand), that will work down into the holes. Be careful when spraying Round Up. If you step in Round Up and then walk in your grass, you may later find dead spots that look alot like foot prints. Crab grass is an annual so should be prevented by a pre-emergent in the spring. A grassy weed that persists over winter is a perenial and can be very carefully spot sprayed with Round up. Take a piece of card board and make a hole in the center. Lay it on the lawn so that only the weed grass shows and then spray. It's been years since I worked in lawn care, so there may be some better advice out there. | 
