If you simply typed in "Dallis" and not "Dallis grass" you may not get anything, but "Dallis grass" returns tons of websites, unfortunately not all what you really want.
Dallis grass, according to what I read, prefers damp soils and a pre emergent (Corn Gluten Meal) spread early will help control it as will getting the soil it is growing in into something more healthy, ie less wet.

Here is a link that might be useful: Dallis grass

i can tell you from experience that Dallis grass grows wet or dry. a pre-m treatment followed up by spot spraying is the only way to really get it under control unless you want to kill teh whole yard and start over.

last year Dallis was taking over my yard. i decided to spray 2 acres with glyphosphate, and leave 2 acres as a control. the 2 acres i sprayed grew back nothing but the bermuda and so far this year no Dallis has popped u, but of course it is usually a little later before it does. in the control area, the Dallis would get so tall between mowings that at times it would lay down under the tractor and not even get cut. it spread so thick that almost sprayed that area as well.

using my method also depend on your type grass. bermuda and certain other grasses die off but almost immediately WILL grow back better than ever after a dose of glyphosphate, whereas other grass type will die and never come back. you have to reseed the entire lawn.

I am having the same battle in my backyard. What I found thru research on the web was that crabgrass killer with MSMA is also supposed to work on Dallis grass. I sprayed a little over a week ago (probably 25% of my backyard) and they are definitely turning yellow--even the Round-Up I tried last year didn't seem to have that much effect. The product I bought advised that retreatment may be necessary after 7-10 days, so I plan to spray again within the next few days. I hate these things!! Pre-emergent doesn't kill the existing one and since they are perennials, they keep coming back bigger every year!

Here is a link that might be useful: Go to the bottom of the page