Gly Pho-Sel Pro 41% with Surfactant would be a good product to use. Taking care to not spray the desirable plants as it is non selective and will kill anything that is sprayed.
There is not a product available that will kill the zoysia without also harming the bluegrass. In this case it is best to spot treat it with a non selective such as GlyPhoSel Pro and then reseed the KGB. Also just to kill off the zoysia completely in his lawn. It might take a few applications and would be best in the spring as it starts to green up or fall when it is going into dormancy. You can reseed the areas 2 weeks after treating.
Gly Pho-Sel Pro 41% with Surfactant mixing rates vary depending on the target weeds
Please review the product label for complete application instructions
It is advised to wait at least one week after applying Gly Pho-Sel 41% with Surfactant before applying a fertilizer to the treated area.
Gly Pho-Sel Pro 41% with Surfactant only kills what is sprayed directly but can have soil residual up to 2 weeks after application.
Yes, Gly Pho-Sel Pro is a non-selective herbicide, so it will kill just about anything it is applied to, including poa. Keep in mind that it will also kill desirable vegetation as well.
No, Gly Pho-Sel Pro 41% with Surfactant is not labeled to be used in aquatic sites. Instead, you can use Rodeo Herbicide as it has been formulated to be used in aquatic sites.
For fence row control of Autumn Olive, Crossbow Herbicide would be a great option. You can also use a non-selective herbicide such as Gly Pho-Sel Pro 41% with Surfactant for this weed as well as Poison Ivy and Russian Olive.
Gly Pho-Sel Pro 41% with Surfactant is a non-selective post-emergent herbicide that will kill most weeds and grasses. Do not treat any desirable turfgrass.
Unfortunately it does not appear that there is any selective herbicides labeled for this type of weed. In your situation it is recommended to spot treat the couch grass with Round Up and kill it directly, and then replant bluegrass in those areas. As long as you do not spray the foliage of the sycamore tree directly, it will not be harmed.
Gly Pho-Sel Pro 41% with Surfactant would only be good to kill everything that is actively growing at the time it is applied. To keep weeds out of the area for up to 1 year you would need to use something like TVC which is a vegetation management product. Keep in mind that it can be very difficult to get herbicides down into the soil where there is gravel since the gravel is porous and often absorbs most of the active ingredient before it can get to the soil below.