What are these bugs flying above my grass?

We recently laid trial turf - a mix of buffalo and kikuyu. Every morning there are hulking shiny black bugs flying in big circular sweeps over the grass - lots of them. The don't stop long ample to have a moral look, but they seem something like 4cm long and have pointy bottoms!

Any belief what they are and whether they are a bad, dull or good item for the grass? If they are bad, what can I do to seize rid of them?

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Answers:    I'd call the place you get the turf from and tell them it was/is infested. They should donate to remedy the situation --- at the very smallest, they should be able to describe you what they are.
If that doesn't work, Lowe's and Home Depot have a catalog from Ortho that shows pictures and what chemical will exterminate pests. You could check there.

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grass bugs! *laughter*

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