How do I get rid of ants nests in the lawn ?

[gfingers]

I think I have 'Lasius Negletus Ants' in 3 sections of my lawn. There are 13 ant mounds in total, 9 of which have appeared last week. The rest started last year but I thought they were probably mole hills up until I noticed all the ants on the surface of them all last week. Then both winged and worker ants disappeared a few days ago leaving all the mounds (which I think are nests) intact.
Is it too late to kill the nests now, have I got to wait until they appear on the surface next year ?

[Buenchico]

From the website of the Royal Horticultural Society:
http://apps.rhs.org.u.../Profile.aspx?pid=503

Chris

[sidkid]

A thread from last July...
http://www.theanswerb.../Question1154816.html