I was not allowed to upload a photo to this site.

Reporter
Oct. 8, 2011, 7:31 a.m.

Thanks for reporting this, Margaret. Water hyacinth is not a listed noxious weed in Oregon. Thus, it's completely legal to grow it, transport it or sell it; indeed it's sold quite widely as an ornamental pond plant. The good news is that water hyacinth is not tolerant of cold temperatures, dying out at temperatures below about 54 degrees F. Since our temperatures tend to get much lower than than most years, it's unlikely this plant would become a nuisance here as it has been across much of the southern reaches of the U.S. As an example: a number of years ago, there was a report of water hyacinth in a cooling pond near Longview, Washington. Even with the elevated water temperatures at that site, the plants still died off during a particularly harsh winter.

Thanks again for keeping an eye out for potentially harmful species and for taking the time to report this. Let me know if you have any questions.

Best Regards,
Vanessa Morgan

--
Vanessa Howard Morgan, Research Assistant
Center for Lakes & Reservoirs, Portland State University
503.725.2937 phone 503.725.3834 fax
www.clr.pdx.edu

Vanessa Howard Morgan
Oct. 10, 2011, 6:12 a.m.

Margaret, It sounds as though you're very familiar with this species, but if you'd like to send a photo for verification, feel free to send it directly to vhoward@pdx.edu (in case this website won't allow you to upload it).

Thanks again,

Vanessa

Vanessa Howard Morgan
Oct. 10, 2011, 6:15 a.m.