From Las Vegas Review-Journal Gardening column:
"Rid lawn of spurge
Fall is a good time to go after these two weeds. Use 2,4-D or some other derivatives to zap them before they disperse their seeds. Before applying the chemical, irrigate the lawn. Do not irrigate or walk on the lawn for the next 24 hours to give the chemical time to eradicate the weeds. Follow the written directions to get the best kill and to protect the environment. These weeds may be a problem next spring if they seeded before. Apply a pre-emergent chemical in February. "
From Ace Hardware:
"This is a tough one but here are some ideas: One of the best control measures for spotted spurge in turf is to maintain a competitive stand of grass. Where open areas develop in the turf either from stress, disease, insects or abuse, light is able to penetrate to the soil surface, allowing spotted spurge to germinate. One spotted spurge is established, altering cultural practices (mowing height, fertilization or irrigation) will not control it, but raising the mowing heights in tall fescue or perennial ryegrass to 2 inches or more may reduce initial invasions.
Pre-emergent herbicides are helpful in reducing establishment of spotted spurge if they are applied in late winter before weed seeds germinate. Check the soil temperature to make sure the herbicides are applied before soil temperature at 1 inch exceeds 55 to 60 degrees. Pre-emergent herbicides for spurge in turf include pendimethalin (Pendulum), isoxaben (Gallery), DCPA (Dacthal), oxadiazon (Ronstar), and dithiopyr (Dimension); of these herbicides, only pendimethalin, dithiopyr, and isoxaben are available for use by the home gardener. Combination products are also available for both the home gardener and professional landscaper; examples include trifluralin plus benefin and oryzalin plus benefin.
Two post-emergent contact herbicides, bromoxynil (available for commercial use only) and glufosinate (available for both commercial and home landscape use), can be applied to spotted spurge plants to reduce populations. Hope that this helps. "
Hope these help!! Good luck.