I have received literally hundreds of calls about ants this year. Yards, houses and people’s lives have been attacked by these somewhat beneficial eusocial insects. Some yards have been invaded with not only hundreds but thousands of ants. I have seen driveways, pools, walkways and walls coated with ants. And to add insult to injury they love to get into your house. We really don’t know why they prefer one yard over another; they may be lured by old decaying mulch, rotting wood or a thatch lawn. But in the garden and lawn they are tiny rototillers. Tunneling ants turn over as much soil as earthworms do, aerating the soil and redistributing nutrients. Ants are also part of the world recycling crew: acting as scavengers, collecting dead insects and turning them into fertilizer for your soil. However, when they invade our homes they become pests and we look for ways to exclude them from our property. However, this problem has no simple solution and requires many steps to reduce the pest pressure to a livable level and total control may not be necessary. When it comes down to ants in the garden and lawn they have a positive role. The ants, in fact, are eaten by other insects, spiders, frogs, birds, fish, and some mammals, forming an important part of food webs all over the world.
https://www.linkedin.com/pulse/ants-come-marching-randy-bilesky?published=t
http://www.delta-optimist.com/opinion/blogs/blog-the-ants-come-marching-1.2332586