Photo: Russian Olive in southwest Montana. © 2020 Delena Norris-Tull
Doug Johnson, Executive Director of the California Invasive Plant Council (Cal-IPC).
Phone 510-843-3902 x302, Email: dwjohnson@cal-ipc.org
Interview by Dr. Delena Norris-Tull, Professor Emerita of Science Education, University of Montana Western
(Interview reviewed & approved Sept. 29, 2020)
I had a conversation with Doug Johnson in September 2020. I had been trying to make sense of the rather confusing California websites that provide information on invasive species. I had come to the conclusion that the State has more than one list of invasive plants. Doug basically confirmed that, and explained it to me this way. The laws regulating invasive species apply to the California Department of Food and Agriculture (CDFA). So the official State list of noxious weeds is developed by the CDFA.
However, the Cal-IPC focuses on weeds that invade wildlands. So the list of invasive plants maintained by Cal-IPC includes some species not on the CDFA list, and vice versa. Some species listed by Cal-IPC are acknowledged to be useful, for instance as turf grass species or food crops such as olive and figs.
The Cal-IPC list does not have the legal authority that the CDFA list does, but it assists land managers in determining which invasive plants to manage. It also assists nurseries and landscapers in determining which species they should or should not sell or use in landscapes.
I asked Doug which list I should include in my giant table of noxious weeds in Western States. We agreed that I should include both lists in my table. The two California lists combined comprise over 200 species.
The ranking systems are different for the two lists. The Cal-IPC list uses a rating system of Limited-Moderate-High, as a guide for landowners and wildland managers on how to prioritize treatment. The CDFA uses an official rating system (A,B,C,D,Q), established in the California Food and Agricultural Code, which applies to all pests, both plant and animal. Refer to the section “State Lists” for a description of the ratings.
Calflora is an online database of spatial information and photographs of California wild plants, both native and invasive. Individuals can add information and photos to the database. That data is added to the data on noxious weeds in Cal-IPC’s CalWeedMapper online tool. This mapping system enables land managers to export distribution of each species, to assist them in determining which species to tackle in their part of the State.
Doug told me that Peter Rice, research ecologist at the University of Montana, used to have a website on invasive plants, the Montana Center for Invasive Plant Management. It was funded for about ten years by the BLM, but that funding eventually dried up. Montana State University extension service now manages an Invasive Plants program.
The University of Georgia followed up on the Montana work and does a lot of work related to invasive plants nationwide, attempting to help coordinate work between the States. When the Nature Conservancy eliminated their Global Invasive Species Team in 2009, their data was taken on by the University of Georgia. They maintain a map of the USA, at invasives.org, showing which States lists which noxious weeds.
Doug is a member of the Western Weed Coordinating Committee, which meets annually in Las Vegas. The Western States are working to better coordinate their efforts.
To learn more about biocontrol efforts, he suggested I call Paul Pratt, at the USDA ARS lab in Albany, CA. They develop biocontrol agents for Western States. And he suggested I contact Bob Price at the CDFA, for more details on State laws and the State list of noxious weeds.
More California Interviews:
Additional Interviews:
Doug Johnson, Executive Director of the California Invasive Plant Council (Cal-IPC).
Phone 510-843-3902 x302, Email: dwjohnson@cal-ipc.org
Interview by Dr. Delena Norris-Tull, Professor Emerita of Science Education, University of Montana Western
(Interview reviewed & approved Sept. 29, 2020)
I had a conversation with Doug Johnson in September 2020. I had been trying to make sense of the rather confusing California websites that provide information on invasive species. I had come to the conclusion that the State has more than one list of invasive plants. Doug basically confirmed that, and explained it to me this way. The laws regulating invasive species apply to the California Department of Food and Agriculture (CDFA). So the official State list of noxious weeds is developed by the CDFA.
However, the Cal-IPC focuses on weeds that invade wildlands. So the list of invasive plants maintained by Cal-IPC includes some species not on the CDFA list, and vice versa. Some species listed by Cal-IPC are acknowledged to be useful, for instance as turf grass species or food crops such as olive and figs.
The Cal-IPC list does not have the legal authority that the CDFA list does, but it assists land managers in determining which invasive plants to manage. It also assists nurseries and landscapers in determining which species they should or should not sell or use in landscapes.
I asked Doug which list I should include in my giant table of noxious weeds in Western States. We agreed that I should include both lists in my table. The two California lists combined comprise over 200 species.
The ranking systems are different for the two lists. The Cal-IPC list uses a rating system of Limited-Moderate-High, as a guide for landowners and wildland managers on how to prioritize treatment. The CDFA uses an official rating system (A,B,C,D,Q), established in the California Food and Agricultural Code, which applies to all pests, both plant and animal. Refer to the section “State Lists” for a description of the ratings.
Calflora is an online database of spatial information and photographs of California wild plants, both native and invasive. Individuals can add information and photos to the database. That data is added to the data on noxious weeds in Cal-IPC’s CalWeedMapper online tool. This mapping system enables land managers to export distribution of each species, to assist them in determining which species to tackle in their part of the State.
Doug told me that Peter Rice, research ecologist at the University of Montana, used to have a website on invasive plants, the Montana Center for Invasive Plant Management. It was funded for about ten years by the BLM, but that funding eventually dried up. Montana State University extension service now manages an Invasive Plants program.
The University of Georgia followed up on the Montana work and does a lot of work related to invasive plants nationwide, attempting to help coordinate work between the States. When the Nature Conservancy eliminated their Global Invasive Species Team in 2009, their data was taken on by the University of Georgia. They maintain a map of the USA, at invasives.org, showing which States lists which noxious weeds.
Doug is a member of the Western Weed Coordinating Committee, which meets annually in Las Vegas. The Western States are working to better coordinate their efforts.
To learn more about biocontrol efforts, he suggested I call Paul Pratt, at the USDA ARS lab in Albany, CA. They develop biocontrol agents for Western States. And he suggested I contact Bob Price at the CDFA, for more details on State laws and the State list of noxious weeds.
More California Interviews:
Additional Interviews: