El Dorado County

El Dorado County Invasive Weed Management Group

A Builder and Contractor's Guide to Preventing the Introduction and Spread of Invasive Weeds
A Landowner's Guide to Preventing the Introduction and Spread of Invasive Weeds
Selected Invasive Weeds of the Central Sierra Nevada - A Field Guide - 4th Edition April 2007
Don't Plant a Pest Brochure - Sierra Foothills Region
Please Don't Plant A Problem! An invasive weed to watch for: Oblong Spurge Brochure

Invasive Weed Priority List - El Dorado County Invasive Weed Management Group - March 2009

Group 1 - These terrestrial species are: a) not currently found in El Dorado County, or b) documented as small, eradicable populations, or c) deemed controllable along a defined eastern leading edge to prevent spread into the Sierra Nevada Mountains. Encourage active control/eradication efforts and education in El Dorado County.

Yellow starthistle (Centaurea solstitialis); eradicate at 3500 ft. elevation and higher
Spotted knapweed (Centaurea maculosa)
Tall whitetop/perennial pepperweed (Lepidium latifolium)
Dalmatian toadflax (Linaria genistifolia ssp. dalmatica)
Oblong spurge (Euphorbia oblongata)
Tamarisk/saltcedar (Tamarix spp.)
Scarlet wisteria/rattlebox (Sesbania punicea)
Purple loosestrife (Lythrum salicaria)
Canada thistle (Cirsium arvense)
Diffuse knapweed (Centaurea diffusa)
Rush skeletonweed - control at 3500 ft. elevation and higher (Chondrilla juncea)
Hoary cress (Cardaria draba)
Lens-podded whitetop (Cardaria chalepensis)
Purple starthistle (Centaurea calcitrapa L.)
Russian knapweed (Acroptilon repens)
Stinkwort (Dittrichia graveolens) - eradicate at 3500 ft. elevation and higher
Yellow toadflax (Linaria vulgaris)
Giant knotweed (Polygonum ssp.)
Sicilian starthistle (Centaurea sulphurea Willd.)
Meadow knapweed (Centaurea debeauxii ssp. thuilierii)
Dyer's Woad (Isatis tinctoria)
Tocalote/Malta thistle (Centaurea melitensis)

Group 2 - Encourage the management/control of isolated populations of these terrestrial species to prevent further spread in El Dorado County.

Brooms (Scotch - Cytisus scoparius, French - Genista monspessulana and Spanish - Spartium junceum)
Arundo/Giant reed (Arundo donax)
Fennel (Foeniculum vulgare)
Goatgrass (Aegilops triuncaialis)

Group 3 - Other terrestrial species of concern; continue to increase public awareness and encourage control efforts on public and private lands.

Tree of Heaven (Ailanthus altissima)
Himalaya blackberry (Rubus discolor)
Puncture vine (Tribulus terrestris)
Pampasgrass (Cortaderia selloana)
Johnsongrass (Sorghum halepenses)
Yellow sweetclover (Melilotus officinalis (L.) Lam.
White sweetclover (Melilotus alba Medic.)
Medusahead (Taeniatherum caput-medusae)
Italian thistle (Carduus pycnocephalus)
Hedge parsley/Beggar's lice/Velcro stickers (Torilis arvensis)
Bull thistle (Cirsium vulgare)
Klamathweed (Hypericum perforatum)
Yellow starthistle (Centaurea solstitialis); encourage control below 3500 ft. elevation
Big Periwinkle (Vinca major)
Cheatgrass, Downy brome (Bromus diandrus)
Gorse (Ulex europaeus L.)

Watch List - These terrestrial species are under consideration to be added to the Invasive Weed Priority List; more information is needed to evaluate their invasive characteristics and/or ability to growing in western El Dorado County.