Nice. That should work just fine. Here, the problem would be the trench filling in with soil every time it rains heavily. Even though, I still wish I would have done that instead of installing rhizome barriers I bought from a bamboo seller. It has been a big problem containing it, since it has all escaped through the barrier. Kt

Dear BT33 Thank you very much for your inquiry. I suggest you buy a product called Acclaim extra (fenoxaprop-ethyl). It will take out crabgrass easily, and with repeat applications 2-3 weeks apart will knockout the bermudagrass. You will need to go to a turf specialty/supply store (like Lesco) to get this product, I believe. Seeds and stems do travel via vehicles and water. There is little to do to prevent it. It has been happening in nature since the beginning. Again, thanks for the question and let me know if you have more. Respectfully Trey Rogers, The Briggs & Stratton Yard Doctor, YardDoctor.com

Thanks! Since you have many types of weeds, we'll start with what are easier to control, the broadleaf weeds. This late in the season, broadleaf weeds are probably all you can really get control of until next spring. You can start with 2,4-D, or a mix of 2,4-D and other chemicals. There are lots of different brands and mixes out there, so I can't give you a rate. You'll have to look at the label. You said you wanted to use agricultural labeled chemicals, but buffalograss can be killed by high levels of 2,4-D, and an agricultural label may not list the mix rate for buffalograss, instead listing mixing rates for corn or other crops. I would suggest that you buy a bottle labeled for lawns, to get the correct rate. I suggest something like Ortho Weed-B-Gon Concentrate, which you can purchase at a big box store. A bottle will cover 18,000 sq ft, which would be more than enough for an average lawn. Grassy weeds are more difficult. To control annual weeds, you'll want to apply a pre-emergent in the fall and spring. Pre-emergents won't kill what's already there, but it'll prevent new weeds from germinating. Weed seeds tend to germinate in the fall and spring, so you need to get the pre-emergents out on your lawn at those two times. Three pre-emergents I would suggest are Prodiamine (trade name Barricade) or Pendimethalin (Scott's Halts Crabgrass preventer) and Dithiopyr (Dimension). These products may be cheaper at the ag-store. You'll need to check the labels for the rates, but apply once in September, and once in Late March/Early April. That should be a start to get you into next spring. What will be left will be the perennial grasses. It can get tricky to control these, and these are outside of my particular expertise.

"Plenty of trees around so there are areas where there is no sunlight. Could that be a possible reason? I have no idea." See my previous statement: "Moss grows for any of these reasons - soil is compacted and low in nutrients, drainage is poor and the soil stays wet (drought can have a similar impact), excessive shade or soil pH is out of whack (too acidic or too alkaline)." Moss Out for Lawns generally works very fast when applied according to directions......typically just a matter of hours before the moss turns black and is dead. You still need to rake it out, however.