Put them in a plastic trash bag with some household ammonia: a half cup ought to do them in-- overnight. And then, leave the bag (dark colored) out in the sun ----- Original Message ----- From: "Judy Glattstein" <jgglatt@gmail.com> To: <pbs@lists.ibiblio.org> Sent: Sunday, April 18, 2010 2:38 PM Subject: [pbs] Killing Ranunculus ficaria > At this point I have about 10 gallons of plants that I dug complete with > tubers, leaves, and adjacent soil in the black plastic bag and another 5 > gallons still in a bucket. There are more in the ground but this is a > good part of what was there. I do patrol down the intermittent drainage > creek looking for outliers, where tubers have floated downstream and > rooted where they come to rest. >