Ants can be an unsightly nuisance and inspire concern. However they do not directly damage plants but are more a sign that you have another pest problem.
Ants eat the honeydew secreted by aphids, scale insects and other pests. So ant go where there is food and are clever enough to farm aphids by carrying them from one plant to another to increase their food supply.
Ants can burrow into the soil of seedlings disturbing roots.
Prevention and Control
Photo credit Martin LeBar creative commons license on flickr
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