Toxicity of remains of a sago palm?
Just a couple of days ago I found out how incredibly toxic sago palms are, and had to dig mine up for my dog's safety. I completely pulled out the root ball and disposed of the palm (about 12 inches diameter on the trunk, so it was a bit heavy) but did not get out the roots under the root ball maybe 1-1.5 feet deep and probably left a few other smaller roots. Will these remain toxic indefinitely? Do I need to go dig all of that back up, or do they need to be alive to remain toxic?
I have been keeping my dog away from the area and spent a lot of time making sure no pieces of the palm remained (e.g., no little chunks in the dirt), but I wonder how long this will be needed. She's a little yorkie so it wouldn't take much of it to hurt her, but conversely, I don't see her digging 1-1.5 feet in to get to the big roots left under the now removed root ball. Is there anything else I might need to do to protect her?
Man I hated removing that thing, as it has been here probably 30 years and was beautiful, but I just can't take any chances with my puppy.