I never thought about our city lawn as good frog habitat, but it must be a good location for hunting after some rain (and when the lawn is left a little longer). This week there were two HUGE adult wood frogs hopping around in the lawn - the bigger one got away before I got to see it, but the smaller one was almost as wide as it was long.
Seeing this frog, presumably gorging on the abundant insect life in our sunny lawn, reminded me why we don't use any chemicals on the lawn and try to limit chemical use on our property.
Amphibians are very sensitive to chemicals released in the environment.
Unfortunately, lawn care practices could be detrimental to the survival of urban frogs, toads, and salamanders due to the fact that homeowners use many times more pesticides per acre than applied in agricultural areas.
The most important things that you can do to protect amphibians in your yard are:
1) Choose non-chemical weed controls
2) Minimize fertilizer use
3) Minimize pesticide use
4) Provide natural habitat for foraging and corridors
More details can be found in the U.S. Fish and Wildlife Service's Homeowner's Guide to Protecting Frogs: Lawn and Garden Care or on the USFWS website.