Q.How To Safely Eradicate Houttuynia Cordata?
I have a 12-ft x 12-ft area in my front yard that has been taken over by Houttuynia Cordata. I have read that it is a very difficult plant to eradicate and it is now surrounding a two-year old Japanese Maple tree that I treasure – really want to keep safe. Is landscape vinegar a possibility? Digging it out will kill the maple tree. What if I carefully cut it off and cover the area with black plastic – except for around the maple drip-line?

Certified GKH Gardening Expert
It won't harm the Maple. The feeder roots are too deep and far from the surface to be affected by Houttuynia. Unfortunately, killing it off will mean causing harm to the tree.
What I can suggest is to spray undiluted white vinegar ONLY on the target plant. Not in the soil, and not on the tree. This will kill the target, fairly, quickly. Keep doing this to every new instance of the plant will kill it within a few seasons.
should eradication fail... You will have to turn to glyphosate. In the amount that you will need to use it- it will kill your tree as well.