I'm doing an experiment with unmowed St Augustine. Originally I did not think the grass would get taller than 10 inches, but it is easily 36 inches in one spot under a tree. Here is a picture I took last year. The purpose of the experiment was to demonstrate the benefits that lou mentioned above. I stopped mowing in October of 2011. The location is George West, TX on the edge of the Texas desert. Temps are above 95 from mid May through mid October with humidity running 40-50% most of the time. Since then I have only watered the grass when and where it was calling out to me for water. At no time have I watered more frequently than once per week. There is one spot under a tree on the east side of the house where I have not watered at all since 10/2011. In fact that is where the dog picture was taken. At the time it was about 30 inches high right there. Also since then I have not fertilized and used no insecticide or herbicide. As you can see there is no weed pressure at all - and I am surrounded by fields of King Ranch bluestem. There are places in the yard with plenty of bluestem, bermuda, and other weeds, but those areas are not part of this experiment. So the point of mentioning this is that taller St Aug will resist all the problems you might have with anything else. I always suggest people weld their mower at the highest position to prevent your well-meaning brother in lawn from doing you a favor and scalping your lawn back down "to where it should be." Tall St Aug (4 inches, not 40) is very lush looking and will solve your problems. Another issue you should watch for is drought stress near the sidewalk. Sidewalks take up sunlight all day and remain warm much longer that the soil under the grass. The soil near the sidewalk will get warmer during the day and remain warm until the next day. This tends to drive off the moisture through evaporation near the sidewalk and dry out the grass. The solution is to water more deeply, not more often. Generally I agree that your only problem is the grass roots are not up to speed yet. Give it another month and take another picture to compare. You should see improvement. Set your mower high, water deeply and infrequently, and fertilize and you will have a lawn like your neighbor. I prefer organic fertilizer because I am lazy and don't like to measure, but you can use chemical and get good results, too.

Can you tell us how much and how often you are watering? And how high and how often are you mowing the grass?

Actually, I'm sorry to recommend tightening the purse strings in such an economy but you might recommend if she attend religious services or some type of social club to ask for someone in her neighborhood at those functions. They are liable to have simply applied too much weed killer in an area and killed the grass. As her friend monitor the service for her and help her make new arrangements if need be. Since I've been on disability I have a budget so tight that every time I need to buy something I think it over, over and over. And furthermore, before I moved into this house (by the way I save money compared to government HUD rent and will own this house in 15 years although most home buyers lucky for me scoffed at this house as it's not a new one and requires minor improvements) I lived in government HUD apartments and the government housing professional caretakers were frankly a negligent disaster. In fact the Somerset Housing Authority lost a 3 million dollar law suit after they had residents pleading to remove a large unstable tree but they ignored the pleas and the tree fell on an innocent pregnant woman and killed her. They actually have the nerve to appeal the decision but I expect they'll loose. In my time there I had to complain repeatedly about the neighbors dropping heavy things all day and night on my ceiling and infesting the apartment building with bed bugs! I also called the police on several occasions. I witnessed professional exterminators come in a spray a squirt or two of insecticide in the apartment knowing that was useless. I told them about trees and plants growing to the apartment gutters where the grounds maintenance was so negligent and a year later no change. I watched the meter readers fabricate false meter readings for both electricity and natural gas. I had to go to their office and challenge the false readings. I had to good to their office and file complaints against the exterminators. I had to go to their office and file complaints against the neighbors. I eliminated the bed bugs and roaches myself by cutting off the central heat and not using the gas stove for 3 months and washing everything multiple times, including the inside of the vents with Pine Sol. The roaches and bed bugs simply avoided the cold and Pine Sol and stayed in the neighbor's apartments that weren't killed by the Pine Sol and lack of food not that they need much. The above are 'services' from college educated professionals in service to the US government so help out your neighbors when you can. A university professional isn't smarter than you. They are simply educated in a niche that you aren't. And look at US government in Congress and the President and Wall Street and tell me you're going to listen to them and accept everything they say automatically? No way! They sound like the banal comments section on YouTube or 1/2 dozen other web sites. And these lawn service give people with no experience and often no real interest in horticulture jobs caring for lawns simply because they applied for work. Lots of times you don't get what you paid for.

I have a sloped back yard around my pool, which is much more steep than your slope in the pictures, covered in St. Augustine. I too detest lawns, but I have no money right now, so my St. Augustine is here to stay. I water my St. Augustine with an irrigation system on my allotted days and once yearly treat with weed/feed. Yes, my St. Aug is great on bare feet and very healthy looking. I have no problems with maintaining it on the slope. I'm not bragging, I'm just trying to explain that I have personal experience with this situation. I think your first problem is with the underlying sand. My underlying soil is a thick layer of decayed organic material, on top of a thin layer of sand, on top of a thick layer of loose clay. It's clear from your photos that the mower tires are disturbing the St. Aug's growth. That is very easy to do regardless of the underlying soil, but especially easy in sand such as you have. I think your second problem is with your lawn guy. Seriously. And, I mean absolutely no offense. Your lawn is covered in weeds. It didn't happen overnight, although sometimes it might seem that way. Your lawn guy should know (1) how to mow on a slope without destroying the roots, (2) how to point out a weed problem before it becomes a massive weed problem like you have. How convenient for him that you need sod replacement?!?! Isn't his job routine lawn care, not routine lawn destroying and replacement? That being said, I have a cheap temporary solution for you. I see in the first picture, to the left of the hose/brick path, you have a bush/tree surrounded by a small circle of mulch. And, in the second picture, you have another tree just down slope from the pool, surrounded by another small circle of mulch. I would take a sharp straight-edged shovel and cut away shovel sized squares of sod in a circular pattern around those trees. Making much, much larger circles around the trees. Take a section of the sandy/weedy area, cover thickly in newspaper, wet newspaper, then lay your homemade sod squares on top of the wet paper. Water daily until they take root and can survive on their own. Go back and extend the mulched area around the two trees, so your weed problem doesn't extend under the trees. This should really be done in stages, because the sod squares that you cut out and move need to be kept wet during the moving process. I say my solution is cheap, because you can buy mulch for $1.68 at the big box stores these days, and you would probably need 10 bags. Less than $20. Of course you will have a little extra water expense from having to water daily to establish the newly sodded sections. It is a little bit back breaking, but I'm sure you can either do it or find someone to help. I say my solution is temporary because, ideally, you could eventually plant some sort of hearty, Florida friendly ground cover over that entire area. In the long run it will not require as much water or care as St. Augustine, and you can get rid of the expensive lawn guy! Things to remember: Don't put any weed and feed down on the newly sodded sections either immediately before or after laying the sod. Don't forget to water daily until the new sections have taken hold. Especially during this, our driest time of year. If you choose to use RoundUp on the weedy areas before moving the grass squares, don't lay the grass squares directly on the area treated with RoundUp unless you put in a layer of newspaper or cardboard first. If you can get your hands on some liriope, you could make a border along the brick walk (at the top of the slope), to help hold it all together. Their roots tend to spread out rather than down, so it will keep slope erosion in better check. Lastly, don't let that man with the mower anywhere near the new section. Weed-whacker only until it's established. You probably won't need to mow this area for the next 6 weeks anyway. Maybe someone else will have a better/easier solution, but this is what I did and it works. I certainly welcome any criticism or comments on my suggestion.