Weed Locating with CalWeedMapper


CalWeedMapper showing areas where artichoke thistle is found

How do you know a weed is a weed? My spinach plant looks like a weed – but it isn’t. The pretty ground cover out under the evergreen has dainty pink flowers and doesn’t look like a weed – but it is.

Dodging the Pampas Weed Bullet

I was gazing at the pampas grass seed packet and counting my lucky stars, thinking “what if I hadn’t dodged this bullet and stumbled onto the site that quoted New Zealand’s experience with this invasive plant?” Could I have caused an outbreak of pampas across our stretch of desert? Would my weed seeding have been irreversible?

(The short answers are “you would have a yard full of pampas grass” and “possibly” and “you give yourself far too much credit, Garden Lass.”)

How are we supposed to KNOW?

Through the Weedy Looking Glass

I set out on a mission to find out how a beginning gardener is supposed to find out about weeds – what is a “safe weed,” what is a “noxious weed,” – and quickly ran into the USDA’s Natural Resources Conservation Services and its Invasive and Noxious Weeds section.

I was soon up to my ankles in acronyms. Clearly this was a site designed for people who know exactly what they’re looking for and how to find it. The only thing user-friendly I could find on the page was a link to “Printer-Friendly.” A typical Wyoming noxious weed entry read:

CEDI3 Centaurea diffusa Lam. diffuse knapweed NW L48 (I), CAN (I)
ELRE4 Elymus repens (L.) Gould L48 (I), AK (I), CAN (I), GL (I), SPM (I)
which turns out to be a Monocot of the Poaceae Family, of Perennial duration, with a growth habit of Graninoid. Trust me.

The upside is you could learn a LOT about your area’s weeds on this site. The downside is that you might not want to be a beginning gardener when you tackle this. After 30 minutes of flopping from page to page, looking for something I understood, I gave up and got a new cup of coffee. Won’t cure my headache, but it’ll give me something to throw at the computer screen.

Easier Way to Find Weed Info

Enter CalWeedMapper, courtesy of the California Invasive Plant Council (Cal-IPC). I don’t know how I stumbled into this, but I’m glad I did.

CalWeedMapper enables natural resource managers, scientists and others to create maps and reports of invasive plant distribution, to identify management opportunities in a county, WMA or region, and to maintain up-to-date species distribution data statewide. CalWeedMapper is integrated with Calflora and Consortium of California Herbaria (CCH) databases, so that new occurrence data submitted to either informs quad data in CalWeedMapper.

This is a scary fun site, this CalWeedMapper interactive map and management tool.

First, it puts all the bureaucratic mumbo jumbo in the background, in links you can get to easily – and get out of easily.

Second, it’s got great big zoomable maps that work in familiar ways. If you’ve ever looked at a Google map, you won’t be lost with CalWeedMapper. It’s intuitive.

Third, it’s searchable in several ways. I wanted information on my county, and found it within minutes. No weeding through (pardon the pun) mounds of Latin and stacks of initials. But if you -want- all the details, they’re there within a few clicks.

Fourth, it’s got pictures of the plants. Handy so I’m not out in the back forty yanking up perfectly good politically correct non-invasive ground cover when I think I’m getting rid of an outbreak of Senecio minimus (Australian fireweed).

Bottom Line

This would be insanely handy for national use if there were a national version. To this end, I searched for weed map – but … well, let’s just say what I found won’t help my gardening career.

Searching on noxious plant mapping keeps bringing me back to more USDA sites. I’m not giving up though! If I find gardener-friendly sites like CalWeedMapper for other states, I’ll add them here.

And a hearty “thanks much!” to Doug Johnson, Executive Director of the California Invasive Plant Council, for taking time out of his busy morning to talk with me about CalWeedMapper and other resources.

Coming up, I’ll be talking about other weed education programs that’ll help us all learn what we can and should not plant, without having to learn Latin or Acronym.

Meanwhile – Happy Friday the 13th, fellow thumbs!