The new runesmithing enchantments have "Your Minions spread Burning Ground on Death, dealing 10% of their maximum life as Fire Damage per second."
The Unique item "Replica Siegebreaker" has this mod except it does 20% max life damage.

How do these mods interact with each other?

Would these effects increase each others max life burning ground up to 40% (two wands and belt)?
or would they drop 3 separate burning grounds?

apparently according to the wiki ground effects of the same type from the same source do not stack so if it did drop 3 different burning grounds it would not work well.