Is the photo clear enough? No responses.

Can you let the grass grow longer and take a picture on a cloudy day? There's too much direct sunlight/contrast to see much of anything. You should be mowing at the mower's highest setting, not the lowest. And is your blade sharp. It almost looks like it is on backwards and you're smashing the grass blades apart with the back of the blade instead of the sharp side. Ask me how I know that (!).

Thank you! I have a lawn service and he just came today so it may be the clippings that are confusing the picture too...I will do what you suggest. I hate to lose my lawn. We have a maintenance company for weed and bug but they cant seem to get a handle on it either...whatever it is. They suggested we put boric acid on it...

Don't do that unless you have a soil test which shows your soil is short of boron. Boron is an essential micronutrient, but it has a fragile limit. Up to a point, it's good. Just beyond that point it becomes a soil sterilizer where nothing grows.

The weed company should at least be able to ID the weed. If they can't then no wonder they can't get rid of it. I would consider (strongly) getting rid of a weed control company that cannot ID a weed while looking right at it.

St Augustine is a very salt tolerant grass. Many grasses and grassy weeds, including crabgrass and dallisgrass, can be killed with baking soda. St Augustine seems to survive baking soda. The method of application is very specific to make it work. You can try this and see if it works.

• Mix some shampoo and some molasses (1 TBSP each) into a pint of water.
• Put some baking soda into a sock.
• Spray the weeds with the soapy water. You should not see water beading up on the weed blades. If the water beads up, then use more soap and spray again. Next, while the grass is wet, hold the sock close over the weeds and squeeze the sock. A very fine dust of baking soda will drift out and land on the wet weeds. DO NOT inhale the dust or get it in your eyes. It is very uncomfortable. If there is a slight breeze, you should be upwind of the weeds. It's easy to completely coat the plants with white baking soda. I don't think you need nearly that much.

I'm not certain why this works but I have a working theory. Baking soda is a non selective fungicide. Many plants have a protective layer of a fungus which keeps things off and makes the plant uninteresting for predators. It also results in hydrophobia (water beading up on the plant). The purpose of the shampoo and molasses is to make the dust stick to the weed. With the dust stuck to the blades, it can go to work as a fungicide and attack the plant. It should die in a few hours. Surfactants are often called "stickers" in the ag business, because they make a product stick to the plant. But if the sticker dries first, it won't stick, so you're going to be juggling the sticker and the sock. The sock works like a very very fine sieve. Squeezing it contains the baking soda and lets some out without dumping a load of baking soda all at once. Too much baking soda on the soil is not a good thing either. So the baking soda dust sticks to the wet plant, kills the protective fungal layer, then the excessive sodium directly on the plant kills the plant.

Here is an illustration of the results. It looks pretty bad, but I think it was mostly crabgrass in the area.