Electric wire question for Electricians

[BearkatHunter]

Do I need conduit?

I'm going to run aluminum URD 4/0 cable to provide power to my shop from a pedestal transformer. Although this is direct burial wire, do I need to encase it in conduit due to fireants?

Thanks.

[Walker]

Easier to replace if ever needed. My wire from my house to my boat lift went bad and was direct burial. I put in conduit after I dug it all up and conduit is not very expensive.