Herbicide Applications
Herbicide applications for county natural lands or rights-of-way.
| Start | End | Location | Open to the public | Product | Notes |
|---|---|---|---|---|---|
| 2025/05/1205/12/2025 | 2025/05/1505/15/2025 | Hall Ranch 2 | No | Milestone and Telar | Treating diffuse knapweed, dalmatian toadflax, houndstongue, thistles, burdock, hoary cress, flixweed, sulfur cinquefoil |
| 2025/05/1605/16/2025 | 2025/05/1605/16/2025 | Boulder County ROW | Yes | Tordon 22K | Spot spraying for eradication species: Russian Knapweed |
| 2025/05/1605/16/2025 | 2025/05/1605/16/2025 | Boulder County and State Highway ROW | Yes | Quinstar 4L | Spot spraying for eradication species: Leafy Spurge |
| 2025/05/0705/07/2025 | 2025/05/1605/16/2025 | Spring Valley Rd (Boulder) | Yes | Ecomazapyr | Cut stump treatment of Russian Olives on roadside for driver and road safety. *POSTPONED* for 5/7 due to weather. |
| 2025/05/1205/12/2025 | 2025/05/1605/16/2025 | Monarch Park - Niwot Trails | Yes | Telar and Vista | *POSTPONED* Touch ups for treatment of curly dock, teasel, prickly lettuce, thistles |
| 2025/04/2804/28/2025 | 2025/05/0105/01/2025 | Agricultural Heritage Center HWY 66 | Yes | Ecomazapyr | Cut stump application to tree near building foundation to prevent tree/tree roots from damaging infrastructure. COMPLETED 05/01/2025 |
| 2025/04/2804/28/2025 | 2025/05/1605/16/2025 | Tommy Thompson - Rock Creek Trail | Yes | Telar and Vista | *STARTED 4/29/25* Spraying for curly dock, teasel, kochia, thistles, hoary cress |
| 2025/05/1205/12/2025 | 2025/05/1605/16/2025 | Ruth Roberts - Ruth Roberts Connector Trail | Yes | Telar and Vista | *POSTPONED* Spraying for curly dock, teasel, kochia, thistles, hoary cress |
| 2025/04/2104/21/2025 | 2025/04/2404/24/2025 | Monarch Park | Yes | Telar and Vista | Spraying for curly dock, teasel, musk thistle. *COMPLETED 4/23/25* |
| 2025/04/1404/14/2025 | 2025/04/1704/17/2025 | Hall Meadows | No | Transline | Application to control diffuse knapweed and increase the biodiversity of a restoration site. |
| 2025/04/1004/10/2025 | 2025/04/1004/10/2025 | Cemex Stone Canyon Property | No | Transline | Early season treatment for Diffuse Knapweed to enhance biodiversity and preserve significant natural communities. *Rescheduled from 4/8 to 4/10. *Completed on 4/10 |
| 2025/04/0704/07/2025 | 2025/04/1004/10/2025 | Golden Fredstrom (Near St. Vrain Rd and 75th St.) | No | Telar - 1.5 oz/acre, milestone - 5 oz/acre | Application to control teasel, houndstongue, Canada thistle, bull thistle, common mullein, diffuse knapweed. Completed on 4/10/2025 |
| 2025/04/0704/07/2025 | 2025/04/1104/11/2025 | Carolyn Holmberg Preserve at Rock Creek Farm | Yes | Imazpyr | Stump applications around historical buildings. *Started & Completed on 4/9/25 |
| 2024/10/2910/29/2024 | 2024/10/2910/29/2024 | Hall Ranch 2 | Yes | Tellar | Spot spraying restoration site |
| 2024/08/1408/14/2024 | 2024/08/1408/14/2024 | Heil Valley Ranch | Yes | Imazpyr | |
| 2024/08/1308/13/2024 | 2024/08/1308/13/2024 | Grassy Top | Yes | Milestone, Telar | |
| 2024/07/2907/29/2024 | 2024/07/3107/31/2024 | Open Sky Loop, Lagerman Reservoir | Yes | Ecomazapyr 2sl and Clearcast | Spot spraying for hairy willowherb. *Rescheduled |
| 2024/07/1807/18/2024 | 2024/07/1807/18/2024 | Heil Valley Ranch | Yes | Quinstar 4SL | Morning spot treatment (before 10 AM) of leafy spurge on roadside and trails. |
| 2024/06/0406/04/2024 | 2024/06/0406/04/2024 | Pella Crossing | Yes | Ecomazapyr 2sl | Spot Spraying Yellow Flag Iris |
| 2024/06/0406/04/2024 | 2024/06/0406/04/2024 | Martin FB | Yes | Ecomazapyr 2sl | Spot Spraying Yellow Flag Iris |
| 2024/06/0406/04/2024 | 2024/06/0406/04/2024 | ZAPF | Yes | Ecomazapyr 2sl | Spot Sparying Yellow Flag Iris |
| 2023/10/2610/26/2023 | 2023/10/2610/26/2023 | Walden Ponds | Yes | Hardball, Telar, Quinstar | Spraying general weeds at Walden Ponds |
| 2023/10/2410/24/2023 | 2023/10/2410/24/2023 | Coalton Trailhead - all trails leaving (Meadowlark, Mayhoffer Singletree, Coalton) | Yes | Hardball, Telar, Quinstar | Spraying general weeds along trails including Meadowlark and Mayhoffer Singletree trails |
| 2023/10/2410/24/2023 | 2023/10/2410/24/2023 | Walden Ponds Trail and Heatherwood Walden Link | Yes | Hardball, Telar, QuinStar | Spraying general weeds along trails, cutting and stump treating Tamarisk around ponds |
| 2023/10/1810/18/2023 | 2023/10/1810/18/2023 | Coal Creek Trail | Yes | Hardball,Telar | Spraying general weeds along the trails. Starting at Flagg Park Trailhead and ending at 120th street. |
| 2023/10/1710/17/2023 | 2023/10/1710/17/2023 | Pella Ponds - Marlette Trails | Yes | Hardball, Telar | Spot spraying along trails and in parking lot |
| 2023/10/1210/12/2023 | 2023/10/1610/16/2023 | Heil Valley Ranch Trails: Grindstone Quarry, Lichen Loop, Overland Loop | Yes | Milestone, Quinstar, Hardball & Telar | Spot spraying general weeds and bindweed along the trails. |
| 2023/10/1110/11/2023 | 2023/10/1110/11/2023 | Heil Valley Ranch Trails: Grindstone Quarry, Lichen Loop, Overland Loop | Yes | Milestone, Quinstar, Hardball & Telar | Spot spraying general weeds and bindweed along the trails. |
| 2023/10/0510/05/2023 | 2023/10/0510/05/2023 | Carolyn Holmberg Preserve at Rock Creek Farm, Rock Creek Trail and Cradleboard trail. | Yes | Hardball, Telar, Quinstar | Spot treatments |
| 2023/09/2809/28/2023 | 2023/09/2809/28/2023 | Carolyn Holmberg Preserve at Rock Creek Farm and Rock Creek Trail | Yes | Telar & Hardball | Spraying general weeds including Teasel and Canada Thistle. |
| 2023/09/2609/26/2023 | 2023/09/2609/26/2023 | Carolyn Holmberg Preserve at Rock Creek Farm and Rock Creek Trail | Yes | Telar & Hardball | Spraying general weeds including Teasel and Canada Thistle. |
| 2023/09/1809/18/2023 | 2023/09/1809/18/2023 | Heil Valley Ranch | Yes | Method, Telar | Spraying Leafy Spurge |
| 2023/09/2109/21/2023 | 2023/09/2109/21/2023 | Cline | Yes | Milestone, Telar | Spraying general weeds, specifically Canada Thistle |
| 2023/09/1309/13/2023 | 2023/09/1309/13/2023 | Cougar Trail | Yes | Ecomazapyr, Clearcast | Spraying hairy willowherb |
| 2023/09/1309/13/2023 | 2023/09/1309/13/2023 | Oxford Rd and 95th | Yes | Ecomazapyr, Clearcast | Spraying hairy willowherb |
| 2023/09/1309/13/2023 | 2023/09/1309/13/2023 | Heil Valley Ranch | Yes | Ecomazapyr, Clearcast | spraying along sections of creek for hairy willowherb |
| 2023/09/1309/13/2023 | 2023/09/1309/13/2023 | Isabelle Rd | Yes | Ecomazapyr, Clearcast | Spraying hairy willowherb |
| 2023/09/1309/13/2023 | 2023/09/1309/13/2023 | McLachlan Creek | Yes | Ecomazapyr, Clearcast | spraying hairy willowherb |
| 2023/09/1309/13/2023 | 2023/09/1309/13/2023 | Jay Rd | Yes | Ecomazapyr, Clearcast | spraying hairy willowherb |
| 2023/09/1309/13/2023 | 2023/09/1309/13/2023 | N 63rd Road | Yes | Ecomazapyr, Clearcast | spraying hairy willowherb |
| 2023/09/0509/05/2023 | 2023/09/0509/05/2023 | William Merlin | Yes | Telar | Spraying Telar for general weeds at Williams Merlin off of Peak-to-Peak Highway. |
| 2023/08/2908/29/2023 | 2023/08/2908/29/2023 | Meeker Sort Yard | Yes | Milestone | Spraying Meadow Hawkweed at the Meeker Sort Yard and adjacent county roads. |
| 2023/08/1008/10/2023 | 2023/08/1008/10/2023 | Isabelle Road | Yes | Rodeo | spraying for hairy willowherb on roadside |
| 2023/08/1008/10/2023 | 2023/08/1008/10/2023 | Carolyn Holmberg Preserve at Rock Creek Farm | Yes | Rodeo | Sterns Lake emergency outlet. Spraying for Hairy Willow Herb. |
| 2023/08/1008/10/2023 | 2023/08/1008/10/2023 | Nelson Road & 65th Street | Yes | Rodeo | Spraying Hairy Willow Herb. |
| 2023/07/3107/31/2023 | 2023/08/0308/03/2023 | Mud Lake, Tucker, County road 126 | Yes | Cimmaron 1.5 oz/ac, MSO 64 oz/ac, Hardball 24 oz/ac, Telar 1.5 oz/ac | Spraying for oxeye daisy, canada thistle, and yellow toadflax |
| 2023/07/3107/31/2023 | 2023/08/0308/03/2023 | Caribou Ranch | Yes | Cimmaron Plus 1.5 oz/ac, MSO 64 oz/ac, Harball 24 oz/ac, Telar 1.5 oz/ac | Treating along riparian corridor as well as meadow and Sherwood gulch for oxeye daisy, yellow toadflax, and canada thistle |
| 2023/07/2707/27/2023 | 2023/07/2707/27/2023 | Nederland Community Sort Yard | Yes | Cimarron Plus | |
| 2023/07/2707/27/2023 | 2023/07/2707/27/2023 | Rogers | Yes | Cimarron Plus | |
| 2023/07/2507/25/2023 | 2023/07/2507/25/2023 | CR 97 and Caribou Rd | Yes | Milestone | Spot spraying for orange hawkweed |
| 2023/07/2507/25/2023 | 2023/07/2507/25/2023 | Renalds Ruth | Yes | Milestone | Spraying orange hawkweed |
| 2023/07/2607/26/2023 | 2023/07/2607/26/2023 | Nelson Road | Yes | Rodeo and Sunwet | Spraying Hairy Willowherb. |
| 2023/07/1807/18/2023 | 2023/07/1807/18/2023 | Mud Lake | Yes | Cimarron Plus & MSO | Spraying for Oxeye Daisy and Yellow Toadflax. Will be working along county road 126. |
| 2023/07/1807/18/2023 | 2023/07/1807/18/2023 | Schimdt Trust | Yes | Quinstar & MSO, Cimarron plus & MSO | Spraying for Leafy Spurge and Yellow Toadflax. |
| 2023/07/1907/19/2023 | 2023/07/1907/19/2023 | Open Sky Loop Lagerman Agricultural Preserve | Yes | Rodeo and Sunwet | Spraying for Hairy Willlowherb. |
| 2023/07/1207/12/2023 | 2023/07/1207/12/2023 | Carolyn Holmberg Preserve at Rock Creek Farms | Yes | Rodeo | Treatment of lake dam spill way for safety. |
| 2023/07/1107/11/2023 | 2023/07/1107/11/2023 | Somerset Trail | Yes | Weedmaster and MSO [64 oz/acre] | 7:00 am - 4:00 pm. Applications will be conducted along the edges of the trail. Spraying general weeds. |
| 2023/06/2906/29/2023 | 2023/06/2906/29/2023 | Jasper Rd. | Yes | Rodeo | Treating for Hairy Willowherb |
| 2023/06/2906/29/2023 | 2023/06/2906/29/2023 | Nelson Rd. | Yes | Rodeo | Treating Hairy-willow herb |
| 2023/06/2706/27/2023 | 2023/06/2706/27/2023 | Boulder Canyon Trail | Yes | Weedmaster, Rodeo | Spraying various general weed patches and clearing poison ivy from trail |
| 2023/06/2006/20/2023 | 2023/06/2006/20/2023 | Tommy thompson | Yes | Vista hardball sulfentrazone dicamba | |
| 2023/06/1406/14/2023 | 2023/06/1406/14/2023 | Mayhouffer | Yes | Telar hardball | |
| 2023/06/1406/14/2023 | 2023/06/1406/14/2023 | Monarch park | Yes | Telar hardball | |
| 2023/06/1406/14/2023 | 2023/06/1406/14/2023 | Walden ponds | Yes | Ecomazapyr, Clearcast, Rodeo | Spot spraying for yellow flag iris |
| 2023/06/0806/08/2023 | 2023/06/0806/08/2023 | Niwot trail | Yes | Quinstar | Spraying for leafy spurge |
| 2023/06/1406/14/2023 | 2023/06/1406/14/2023 | Pella Ponds | Yes | Ecomazapyr, Clearcast, Rodeo | Spraying for Yellow flag Iris |
| 2023/06/0706/07/2023 | 2023/06/0706/07/2023 | Heil Valley Ranch | Yes | 2,4-D, Dicamba, Chlorsulfuron | Treatment of Curly Dock will take place in the meadow and along trail edges North of the lower parking lot. |
| 2023/06/0806/08/2023 | 2023/06/0806/08/2023 | Walden Ponds/Duck Pond | Yes | Ecomazaypyr/Clear Cast | Spot spraying Cattails for access purposes. Treatment will be done before 12 PM. |
| 2023/06/0206/02/2023 | 2023/06/0206/02/2023 | Heil Valley Ranch | Yes | 2,4-D, Dicamba, Chlorsulfuron | Treatment of Curly Dock will take place in the meadow South of the lower parking lot and along the roadsides of Geer Canyon Dr. |
| 2023/05/3005/30/2023 | 2023/05/3005/30/2023 | Monarch | Yes | Telar vista hardball | |
| 2023/05/2605/26/2023 | 2023/05/2605/26/2023 | Heil Valley Ranch | Yes | 2,4-D, Dicamba, Chlorsulfuron | Treatment of Curly Dock will take place in the meadow North of the lower parking lot and along the roadsides of Geer Canyon Dr. |
| 2023/05/2505/25/2023 | 2023/05/2505/25/2023 | Tommy thompson | Yes | Telar vista dicamba | |
| 2023/05/2305/23/2023 | 2023/05/2305/23/2023 | Kraft | Yes | Quinstar | Leafy spurge work on property. Work will wrap up by noon. |
| 2023/05/2505/25/2023 | 2023/05/2505/25/2023 | Longmont Boulder Trail and local connections | Yes | Weedmaster, Sulfentrazone | 7:00 am - 4:00 pm. Applications will be conducted along the edges of the trail. Application will start at the crossroads of the Diagonal Hwy and 83rd Street, and end at Lookout Rd and 71st Street. Local connections are the Niwot Trail system, including Cougar Trail and 95th Street. |
| 2023/05/2205/22/2023 | 2023/05/2205/22/2023 | Heil Valley Ranch | Yes | Quinstar | Spot applications for leafy spurge near schoolhouse and lichen loop trails. Morning application. |
| 2023/05/1705/17/2023 | 2023/05/1705/17/2023 | Tommy Thompson | Yes | Telar | Curly dock control |
| 2023/05/0105/01/2023 | 2023/05/0105/01/2023 | Heil- Schoolhouse Loop | Yes | Weedmaster | Morning application until noon, along trails |
| 2022/12/1212/12/2022 | 2022/12/1212/12/2022 | Dodd Reservoir, Monarch Park, Bald Mountain | Yes | Plainview | Bare ground application in and around parking lots |
| 2022/12/0812/08/2022 | 2022/12/0812/08/2022 | Lagerman Reservoir, Monarch Park | Yes | Plainview | Bare ground application in and around parking lots |
| 2022/12/0712/07/2022 | 2022/12/0712/07/2022 | Heil Valley Ranch, Dodd Reservoir, Lagerman Reservoir | Yes | Plainview | Bare ground work in and around parking-lots, walking paths. |
| 2022/12/0612/06/2022 | 2022/12/0612/06/2022 | Heil Valley Ranch, Altona School House | Yes | Plainview | Bareground work in and around parking-lot and walking paths. |
| 2022/11/0711/07/2022 | 2022/11/0711/07/2022 | Walden Ponds | Yes | Glyphosate | We will be doing tree removal within the Critical Wildlife Habitat |
| 2022/11/0211/02/2022 | 2022/11/0211/02/2022 | Walden Ponds | Yes | Milestone, Quinstar, Rejuvra | This treatment will be along the trails |
| 2022/11/0111/01/2022 | 2022/11/0111/01/2022 | Hall Ranch | Yes | Rejuvra | Aerial application - park closed |
| 2022/10/2610/26/2022 | 2022/10/2610/26/2022 | Twin Lakes | Yes | Milestone, Rejuvra | Spray along trail edges |
| 2022/10/2610/26/2022 | 2022/10/2610/26/2022 | Harney Lastoka Trail | Yes | Milestone, Rejuvra | Treatment will be along trail edges. |
| 2022/10/1810/18/2022 | 2022/10/2010/20/2022 | Heil Valley Ranch | Yes | Milestone, Rejuvra | Picture Rock, Wapiti, Wild Turkey, Ponderosa Loop and Lichen Loop Trails |
| 2022/10/1710/17/2022 | 2022/10/1810/18/2022 | Heil - Pyrite trail | Yes | Milestone | Afternoon treatment. Includes the edges of trails |
| 2022/10/1110/11/2022 | 2022/10/1310/13/2022 | Walker Ranch - Meyers Homestead Trail, Walker Loop, Josie Heath Trail | Yes | Milestone, Quinstar, Rejuvra | This treatment will occur along all trails and in trailhead parking lots. |
| 2022/10/2610/26/2022 | 2022/10/2610/26/2022 | Walden Ponds | Yes | Milestone, Rejuvra | This treatment will occur along trail edges and in parking lots. |
| 2022/10/1010/10/2022 | 2022/10/1010/10/2022 | Heil Valley Ranch | Yes | Milestone, Quinstar | This treatment will be done near the corral parking lot and along the road |
| 2022/10/0410/04/2022 | 2022/10/0410/04/2022 | Walden Ponds | Yes | Milestone, Quinstar, Rejuvra, Rodeo, Ecoimzapyr | This application will occur along the trail edges and in the open areas. |
| 2022/10/0310/03/2022 | 2022/10/0310/03/2022 | Bettasso Preserve - Betasso Link trail and Canyon Loop | Yes | Rejuvra | |
| 2022/09/2009/20/2022 | 2022/09/2009/20/2022 | Caribou Ranch & Mud Lake - all trails (Kinnickinnick Loop, Tungsten Loop, Caribou Ranch Link, Blue Bird Loop, DeLonde Trail | Yes | Milestone | |
| 2022/09/1509/15/2022 | 2022/09/1509/15/2022 | Caribou Ranch & Mud Lake - all trails (Kinnickinnick Loop, Tungsten Loop, Caribou Ranch Link, Blue Bird Loop, DeLonde Trail) | Yes | Milestone, Ecomazpry | Work will be done in meadows and along trail edges. |
| 2022/09/1409/14/2022 | 2022/09/1409/14/2022 | Pella Ponds - Trailhead, Marlette Trails and Braly Trails | Yes | Hardball, Telar, Rodeo, Ecoimazpyr | Most of the treatment will be along the pond banks. Some work will be along the trails. Please use caution and watch for employees. All day 7:00am-4:30pm |
| 2022/09/1309/13/2022 | 2022/09/1409/14/2022 | Coalton Trailhead - all trails leaving (Meadowlark, Mayhoffer Singletree, Coalton) trailhead | Yes | Hardball, Telar, Rejuvra | Trail work - please use caution and watch for employees on trail. All day work 8:30-4:00. |
| 2022/09/1309/13/2022 | 2022/09/1309/13/2022 | Rock Creek Farms | Yes | Hardball, Telar, Rejuvra | We will be working in the drainages on the property. Some work will be near the craddleboard trail but not on the trail. 8:30-2:00. |
| 2022/09/0809/08/2022 | 2022/09/0809/08/2022 | Caribou Ranch - Large Meadow near Delonde Homestead and along Delonde Trail | Yes | Milestone, Ecomazpry | This treatment will be in the afternoon 12:00-3:30. |
| 2022/08/2308/23/2022 | 2022/08/2308/23/2022 | 4 Mile Canyon, Sunshine Canyon, Dixon Rd., Gold Trail Rd. | Yes | Rejuvra, Milestone | Spot spraying for cheat grass and spotted knapweed |
| 2022/08/1808/18/2022 | 2022/08/1808/18/2022 | Pella Ponds - Marlette Trails | Yes | Rodeo, Ecomazypr | Spot treating along pond banks for Hairy Willowherb. Done by 11:00 am. |
| 2022/08/1708/17/2022 | 2022/08/1708/17/2022 | Anne U. White Trail and Trailhead | Yes | Roundup Pro | Spot treating along trail in the morning. Done before 12:00 pm. |
| 2022/08/1008/10/2022 | 2022/08/1008/10/2022 | Sterns lake trailhead, Mary Miller Trail, Craddleboard trail | Yes | Telar, Hardball, Milestone, Rejuvra, Quinstar | Trail Work. Caution when using trail. |
| 2022/08/0308/03/2022 | 2022/08/0308/03/2022 | Cougar Trail | Yes | Rodeo, Ecomazypr | 8:00 am - 11:30 am. Spot treating for Purple Loosestrife in the area. |
| 2022/07/2607/26/2022 | 2022/07/2607/26/2022 | Caribou Ranch - Large Meadow near Delonde Homestead | Yes | Cimarron Plus | Application will be occurring in the afternoon. After 12:30 pm. Application will not be along trails. |
| 2022/07/2107/21/2022 | 2022/07/2107/21/2022 | Bettasso Preserve - Betasso Link trail and Canyon Loop | Yes | Hardball, Milestone | Treatment will be done in the morning and finish before 1:00 pm |
| 2022/07/1307/13/2022 | 2022/07/1307/13/2022 | Caribou Ranch | Yes | Cimarron Plus | |
| 2022/07/0707/07/2022 | 2022/07/0707/07/2022 | Longmont-Boulder Trail | Yes | Telar, Hardball, Milestone | This application will take place between 8:00 AM and 11:00 AM. |
| 2022/07/0507/05/2022 | 2022/07/0507/05/2022 | Arapahoe Rd., Jasper Rd., Hwy. 287 | Yes | Overdrive, Quinstar, MSO | targeting leafy spurge |
| 2022/06/3006/30/2022 | 2022/06/3006/30/2022 | Dixon Rd., County Rd. 52, 4-Mile Canyon | Yes | Quinclorac, Overdrive, MSO | leafy spurge control |
| 2022/06/2906/29/2022 | 2022/06/2906/29/2022 | Quicksilver Rd., Oxford Rd., E. County Line Rd., Niwot Rd. | Yes | Telar XP, Milestone | Canada thistle, diffuse knapweed and chickory spot spraying |
| 2022/06/1406/14/2022 | 2022/06/1406/14/2022 | Pella Ponds, Sterns Lake, Dodd Reservoir, Gaynor Lake | Yes | Rodeo, ecoimazpyr | Spillway treatment |
| 2022/06/0906/09/2022 | 2022/06/0906/09/2022 | Longmont-Boulder Trail | Yes | Vista, Telar, Sulfentrazone, Hardball, Milestone | 7:30 am -12:30 pm from Lefthand Grange to Monarch |
| 2022/06/0806/08/2022 | 2022/06/0806/08/2022 | Walker Range - All trailheads and trails | Yes | Milestone and Quinstar | Spot spraying around trailhead and trails. |
| 2022/06/0706/07/2022 | 2022/06/0706/07/2022 | Mayhoffer, Meadowlark Trail | Yes | Milestone, Hardball, NIS | Most spot spraying will be done off of the trail. |
| 2022/05/3105/31/2022 | 2022/05/3105/31/2022 | Longmont Boulder Trail | Yes | Vista, Sulfentrazone | Trail between 95th and Left Hand Grange, only afternoon spraying |
| 2022/05/2605/26/2022 | 2022/05/2605/26/2022 | 55th St., 63rd St. | Yes | Harball, Piper | roadside spot spraying |
| 2022/05/2505/25/2022 | 2022/05/2505/25/2022 | Hwy 52 | Yes | piper, Hardball | |
| 2022/05/2505/25/2022 | 2022/05/2505/25/2022 | Longmont Boulder Trail | Yes | Vista, Sulfentrazone, Piper | Afternoon; work done between 95th and lefthand grange. |
| 2022/05/1905/19/2022 | 2022/05/1905/19/2022 | Walker Ranch - Meyers Homestead Trail, Walker Loop, Josie Heath Trail | Yes | Hardball, Weedmaster, Milestone, Rejuvra | This treatment will happen at the trailheads and along the trails. Spot spraying. |
| 2022/05/1905/19/2022 | 2022/05/1905/19/2022 | Pella Ponds - Marlette Trails | Yes | Hardball, Weedmaster | Will be done by 10:30 am. |
| 2022/05/1705/17/2022 | 2022/05/1705/17/2022 | Pella Ponds | Yes | Hardball, Telar, Dicamba | spot spraying |
| 2022/05/1705/17/2022 | 2022/05/1705/17/2022 | CDOT HWY. 52, 55th St. | Yes | Hardball, Piper | roadside spot spraying |
| 2022/05/1605/16/2022 | 2022/05/1605/16/2022 | Oxford Rd., 119th St., Quicksilver Rd., Pipit Rd. | Yes | Hardball, Piper | roadside spot spraying |
| 2022/05/1005/10/2022 | 2022/05/1005/10/2022 | Pella Ponds - Trailhead, Marlette Trails and Braly Trails | Yes | Hardball, Telar, Quinstar, Piper, Vista | This will be a spot treatment along the trail edges and parking lot |
| 2022/05/0505/05/2022 | 2022/05/0505/05/2022 | 75th St., 95th St., Niwot Rd. | Yes | Plainview SC; Piper; Roundup Pro Concentrate | bare-ground application under guardrails |
| 2022/04/2804/28/2022 | 2022/04/2804/28/2022 | 95th St.; 75th St.; Niwot Rd. | Yes | Plainview SC; Piper; Roundup Pro Concentrate | bare-ground application under guardrails |
| 2022/04/2704/27/2022 | 2022/04/2704/27/2022 | Nelson Road; Niwot Road; 63rd Street | Yes | Plainview SC; Piper; Roundup Pro Concentrate | Bare-ground application under guardrails |
| 2022/04/2604/26/2022 | 2022/04/2604/26/2022 | 95th St., 75th St. | Yes | Piper, Hardball | spot spraying, mainly targeting Kochia and Curly Dock |
*Please note that activities before November 2024 were only recorded here for natural areas open to the public.
Mowing Reports
Mowing activities are recorded for Boulder County maintained roads.
| Start | End | Location | Notes |
|---|---|---|---|
| 2025/04/2804/28/2025 | 2025/05/0205/02/2025 | County Maintained roads North of State Highway 66 Between 75th St and East County Line Road. |
Drone Applications
You can sign up to receive email or text notifications about scheduled drone herbicide applications. Notifications will be sent out on the Friday before the week of application. Drones may be used in areas where the terrain is too steep for worker safety, tractors cannot operate safely, or the area is too large for other methods to be practical. They are also ideal for smaller, remote applications in places that are otherwise inaccessible. To ensure safety, drones are operated at least 50 feet away from property boundaries and a minimum of 660 feet (1/8 of a mile) from residential areas and municipal boundaries.
| Start | End | Location | Open to the public | Product | Notes | Map |
|---|