Hi there. I have been working to eliminate Italian Arum from my yard for several months, following the advice and flyers I received from one of your experts earlier this year to dig around it, bag it up with the infected dirt, and make sure it goes in the landfill and not the compost. My neighbor has it as well, and I fear hers will re-spread into my yard going forward, as she's not able to keep up with the removal as much as I am. If I plant a wide (12 inch deep) metal corrugated border between our two yards (or other "rhizome barrier), do you think that that will help control the spread from her yard? I was thinking that because much of the spread happens underground through the rhizomes, this might help control it a bit. There is a fence between the yards, so maybe the spread from the top part of the plant (berries, etc) will not be so bad, either. Thank you!
Multnomah County Oregon
Getting control of Italian arum is difficult. It takes years to eradicate it. Tiny bits of bulbits can create whole new plants. A metal barrier 12 inches deep along your fence should really help stop the spread from your neighbor's garden. You'll still have to watch for new plants coming up in your garden. It takes years to completely get rid of it. This article shows the bulblets and tubers of a dug-up plant, Italian Arum https://www.swcd.net/invasive-noxious-weeds/italian-arum-2/. They are grouped next to the root, so a barrier should help.
As all parts of the plant are poisonous and irritating, please be sure and use protective clothing and gloves when working around the plants, and dispose of all Italian arum in the trash, as you've been doing. There are several articles with information on Italian Arum; this one has good concise advice, Control Options for Italian Arum https://www.whatcomcounty.us/DocumentCenter/View/27070/Italian-Arum-Management.