Okay, that makes sense. Personally, I'd have though a name like 'false
nettle' would have been more appropriate, but the purple dead nettle does
look rather sickly if you ask me so maybe 'dead' is better.

As for the lead, I've read that it doesn't have a lethal toxicity for
healthy adults, and isn't especially harmful for most people, but it's
really insidious for children and the elderly.

The person (who is not a botantist or biologist) who told me about the lead
connection said that there's a plant that's a sure indicator of lead in the
soil. He was pretty sure it was purple dead nettle (which I assume he
meant lamium purpureum). I thought he was confused or pulling my leg, but
then I saw this (on google):

From: phorbin )
Subject: Groundcover
Newsgroups: rec.gardens
Date: 2001-05-20 19:00:59 PST
says...
Try Dead Nettle.....very hardy, lov growing groundcover.....Erin


Eeeuch.... LOL. Bad smell... Toxic stuff.

Mischievous suggestion.

Anyway, thanks for responding.