ST. PAUL (AP) - Minnesota's extended stretch of hot weather has prompted a warning about toxic blue-green algae.

The algae gathers on the surface of the water and is known to kill dogs if they drink enough of it. It can also cause rashes and respiratory problems for people.

Pam Anderson of the Minnesota Pollution Control Agency says people should be aware of the potential for trouble, and make sure kids and pets stay out of water that looks doubtful.

Anderson says blue-green algae feeds off phosphorous and other nutrients that may run into water. People can protect lakes and ponds by minimizing the runoff of yard or farm soil into waterways.

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