Volunteer Weed Watchers

"Looking for the worst plants in the best places."

The Mt. Tamalpais Watershed is part of the Golden Gate Biosphere reserve, an internationally recognized biodiversity “hot spot.” This watershed is home to over 900 species of plants and 400 species of animals, including 77 rare, threatened and endangered species. This abundance of life is threatened by many factors, including increased recreational use, invasive species and global climate change.

Did you know?

• MMWD habitats include oak woodlands, redwood forests, serpentine ridge tops, grasslands and fresh water creeks.
• Just one escaped ornamental jubata grass (Cortaderia jubata) can produce a million wind-dispersed seeds without pollination.
• Western pond turtles nest in open grasslands, which are threatened by invasive broom species.

Starting in 2010, the district began a volunteer program to help survey trails and roadsides for new weed populations, discovering invasive plants before they become well established. Data collected from vegetation monitoring informs the resource management and conservation activities on the watershed.

Being a "weed watcher" is a great way to increase your knowledge of botany, improve your resume and contribute to the protection of habitat on which our native plants and animals depend. Volunteers are trained to identify both invasive and rare plant species and to take location data on paper maps or using GPS units. Volunteers go out as often as they like on the trails of Mt. Tam, either singly, in pairs or on monthly guided hikes.

This year's training classes were held in April and May. (Click here for a full description of the position. )  We will be training more volunteer weed watchers next year. In the meantime, consider volunteering for our trail and habitat restoration events.Thank you!

Survey forms for weed watchers:

Weed Watchers Survey Form (PDF) 

Weed Watchers Detailed Data Sheet (PDF)

Weed watcher maps*:

Airforce Station: I13, I14, J13
Alpine Tr: K13, K14
Alpine-Bon Tempe Pump Rd: F12
Antenna Farm Rd: I15
Arturo Trail: I13
Azalea Hill: E11, E12, E13, F12, H12, H13, I13
Bald Hill: E14, E15
Bare Knoll Rd: I11
Barths Retreat Rd: I12
Benstein: I12, J12, J13
Berry Tr: H13, I13, G13, G14
Big Carson Tr: C08
Big Trees: E08, E09
Bill Williams: F16, G16
Blithdale Ridge Rd: H17
Bolinas Ridge Rd: B02, C02, C03, D03, D04, E04, E05, F05, F06, G06, G07, G08, H08
Bolinas-Fairfax Rd: E11, E12, F10, F11, G08, G10, G11, H08, H09, H10
Bon Tempe Channel: G14
Bon Tempe Dam, Aerator Rd., and Shoreline Tr: F12, F13
Bone Yard: G14
Bourne Tr: G08, H08
Bowling Alley Tr: I13, J13
Boy Scout Rd: E14
Buckeye Tr: D15, D16, E16
Bull Frog Rd: E12, E13, F13
CA Coastal Tr: H08, H09, I09, I10, J10, J11, K11, K12, K13
Canyon Tr: D14, E14
Carey Camp: D10, D11, E10, E11, E12
Cascade Canyon Rd: C09, C10, C11, D11
Cataract Tr: H10, I10, I11, J11, J12, K12
Collier Springs Tr: G14, H14, I14
Concrete Pipe Rd/Tr: E13, E14, F14, F15
Conifer: B08, B09
Continental Cove Rd: B04, B05
Crest Farm Rd: E13
Cross Country Boys Tr: H12, H13, I12, I13
Dam Trail: F13
Deer Park Rd/Tr: D15, E14, E15
Dibblie Rd: F16, F17
Dog Creek Rd: B03
East Peak Fire Tr: G15, H15, H16, I16
Eldridge Grade: F15, F16, G15, G16, H16, H17, I15, I16, I17
Elliot Tr: E14, F14
Fern Canyon Tank Rd: J16, J17
Fern Creek Tr: I15, I16, J15
Filter Plant Rd: F15, G14, G15, G16
Fish Grade: F14, F15, G14, G15
Gertrude Ord Tr: F15, F16, G16
Girl Scout Rd: E13
Grassy Slope Rd: B04
Gravity Car Rd: J16, K16
Happersberger Tr: D10, D11
Harry Allen Tr: G16, G17
Helen Markt Tr: G11, H10, H11, I10
Hidden Cove Tr: F13
Hidden Meadow Tr: E15, F15
High Marsh Tr: H12, I11, I12
Hog Back Rd: J15, J16, K16
Hoo-Koo-E-Koo Rd: H17, I17, J15, J16, J17
Horseshoe Rd: I18
Indian Rd/Tr: G17, H16, H17, I16
Ink Well Tr: C10, C11
Interior Pine Point Rd: F13, G13, G14
International Tr: I14
Junction Tr: E14
Kent Fire Trail: H17
Kent Pump Rd: E07, E08, F08, F09, G09, H09, H10
Kent Tr: F11, F12, G11, G12, H11, H12, H13, I12, I13
Lagoon Rd/Tr: H12, H13, I13
Lagunitas Picnic Area and Dam: G14
Lagunitas Fire Tr: G14, G15, I15
Lagunitas Rock-Springs Rd: G14, H13, H14, I13, J12, J13
Lake Lagunitas Rd: G14, G15
Lakeview Rd/Tr: G14, G15, G16, I14, I15
Laurel Dell Rd: I11, I12, I13, J11
Liberty Tr: E10, E11, F11, F12
Lily Lake-Alpine Lake Rd/Tr: F10, F11
Little Carson Tr: E09, E10
Log Cabin Rd: F16
Madrone Tr: F14, F15
Matt Davis Tr: J14, J15, J16, K13, K14
McKennan Tr: I09, I10
Meadow Club: D12, E11, E12, E13
Meernaa Tr: D15
Mickey O'Brien Tr: I11, I12, J11, J12
Middle Peak Rd: I15
Miller Tr: I14, I15, J15
Moore Tr: E14
Mountain Top Tr: J13
Muir Woods Rd: J15, K15, K16
Myrtle Tr: J17
New Paradigm Tr: C06, C07, D07
Nora Tr: J14, J15
North Knee Tr: I16
Northside Tr: H13, H14, H15, H16, I13, I14, I15, I16
Nudist Nest: G12
Oak Ave: E16
Oat Hill Rd: D10, E10, F09, F10, G10
Old Railroad Grade: I14, I15, I17, I18, J14, J15, J16, J17
Old Sled Tr: E09, E10, E11
Old Stage Rd: J13, J14, K13
Old Vee Rd: F08, F09, F10
Peters Dam: A03, B03, B04
Phoenix Lake Rd: F15, F16
Pilot Knob and Summit Tr: G14, G15
Pine Mountain Rd: B07, B08, C05, C06, C07, C08, D07, D08, D09, D10, E10, E11
Pine Mt Tunnel Rd: D11, D12
Pine Mtn Tr: C09, D06, D09
Pine Point Tr: F13, F14, G13, G14
Plank Walk Tr: I16
Poison Spring Rd: D07
Potrero Meadows Tr: I12, I13
Power Line Access Rd: F06, F07
Pumpkin Ridge Tr: F14, G14
Redwood Spring Tr: I15, I16
Ridge Tr: E14, E15
Ridgecrest Blvd: H08, H09, I09, I10, I13, I14, I15, I16, J10, J11, J12, J13, K11, K12
Rock Spring Tr: J12, J13, J14, K12, K13
Rocky Ridge Rd: F12, G12, G13, H13, I13, I14
Ross Trail: F16, F17
San Geronimo Ridge: A03, A04, A05, A06, B03, B04, B05, B06, B07, B08, B09, C09, D09
School Tr: D15, E15
Scott Tank Rd: E13
Serpentine Knoll Tr: H12
Shadyside Tr: F12, F13, G13, G14
Shafter Grade: A03, B02, B03
Shaver Grade: E14, F13, F14, F15
Sierra Tr: K15, K16
Simmons Tr: I12, J12
Siphon Rd: G16
Six Points Tr: E14, E15
Sky Oaks Rd/Tr: E13, F13, F14, G14
Sky Ranch Tank Rd: D15
Slide Gulch Tank Rd: J17
Sludge Pond Rd: G14
Split Rock Tr: C11, D11, D12
Stocking Tr: G13, H12, H13
Sunnyside Tr: F13, F14
Swimmers Tr: F11
Tamarack Rd: A06
Tavern Pump Tr: I15
Taylor Tr: E13, E14
Telephone Tr: I16
Temelpa Tr: I16, I17, J17
Tenderfoot Tr : K16
Troop 80 Tr: J15, K13, K14, K15
Tucker Tr: G16, G17, H16, H17
Van Wyck Tr: G11, G12, H12, H13
Verna Dunshee Tr: I16
Vic Haun (a.k.a. Airplane) Tr: I16, J16
Water Tank Rd/Tr: I16
West Fork Tr: G14, H14, I14
West Point Trail: J14, J15, K15
Westpeak Turnoff: I14
Wheeler Tr: I16, I17
White Hill Rd: B09, B11, C11
Wildcat Meadow Tr: C09, C10
Willow Camp: J10, J11
Worn Springs: D15, E15, E16, F15, F16
Yolanda Tr: E15, E16, F15, F16
Zig-zag Tr: J16, K16

*These maps were made to assist weed watchers in marking locations of priority invasive plant species. No warrant is made to their accuracy or completeness. They are not intended for use as a navigational aid. They may not be reproduced without acknowledging the Marin Municipal Water District as the original author (including retaining the MMWD logo) or sold for profit. If they are altered from their original form, the new map must clearly state how and when.