Invasive but useful - the story of a weed

In an attempt to identify various plants sprouting up in my landscape, I picked up (highly recommended) "Wild Urban Plants of the Northeast".  Aside from realizing that I had mistaken ragweed for mums (and performing a quick execution), I identified a rather graceful little weed as the Asiatic Dayflower.  This plant has sprouted up in some fairly hostile areas of my lawn, among them an area where the soil is only 2 inches deep (in drought conditions) and on top of an area where roofing tar appears to have been spilled.  The latter area has been a thorn in my side because I want to expand my edible garden to that area and don't trust the soil quality.

Which is why I was interested to find out that this flower is an intense bioreceptor for heavy metals, particularly lead.  This was discovered when the plant colonized tailings ponds in China. 

Of course, I am better off just carting off and replacing the soil from the area, but that is because I have easy and cheap access to replacement soil.  In urban areas where this is not true, cultivating this plant could be highly useful.

Potential pitfalls: the remediation is limited by the root spread of these plants (which seems to be a depth of about 6 inches), and the plants themselves become impacted waste (and if allowed to decompose openly will redeposit the metals). 

The use of these to remediate soil on a commercial scale is limited as well, since contact with the contaminated surface is required. 

But, still.  Pretty darn cool.