Ravalli County Weed District

Ravalli County Weed District We are a department of Ravalli County. Our mission is to manage the noxious w**ds within the County.

We work towards this goal through education, on the ground work, and prevention.

W**d of the week for -Montana's Noxious W**d Awareness Week. Ravalli county has plenty of this. We all need to work toge...
06/07/2026

W**d of the week for -Montana's Noxious W**d Awareness Week. Ravalli county has plenty of this. We all need to work together to get this one gone. Pretty but pretty bad and very invasive.

https://www.facebook.com/share/1CvWfgNdcH/
05/24/2026

https://www.facebook.com/share/1CvWfgNdcH/

WHAT KIND OF HERBICIDE SHOULD YOU USE TO KILL YOUR W**DS?

A lot of people hear the word “herbicide” and sometimes assume that all w**d sprays are basically the same. They are not. Different herbicides are designed to do very different jobs. Here is some information to help you know what herbicide you should use to control w**ds on your property.

I put this information together because we have been getting a lot of basic questions about "w**d sprays" lately at our Madison County W**d District office and it seems like perhaps putting some basic herbicide information in a Facebook post would give folks something to save and refer back to the next time that they are shopping for "w**d spray". Hopefully, these basic descriptions of different kinds of herbicides can help you.

Keep in mind, herbicides are designed to work in very specific ways and the labels reflect that. If you do not follow the label, you will cause unintended damage, so follow the label. THE LABEL IS ACTUAL LAW.

-- TYPES OF HERBICIDES -- The Basics

SELECTIVE vs. NON-SELECTIVE

• SELECTIVE Herbicides: These target certain types of plants while leaving others mostly unharmed.

Example: A lawn w**d killer that kills dandelions and thistles but leaves the grass alive.

Why use them? When you want to remove w**ds WITHOUT killing desirable plants like lawns, pasture grass, or certain crops.

Common uses:
-Lawn w**d control
-Pasture w**d control
-Crop production
-Rangeland management

• NON-SELECTIVE Herbicides: These kill or injure MOST plants they contact.

Example: Products used on gravel driveways, fence lines, industrial sites, or before reseeding.

Why use them? When you want total vegetation control or need to clear an area completely.
Important note: Homemade vinegar/salt/dish soap w**d spray mixtures also function as non-selective treatments and will damage or kill most plants they contact.

Common uses:
-Gravel areas
-Fence lines
-Very targeted spot spraying of invasive w**ds
-Site preparation before planting

HERBICIDE “GROUPS” (MODE OF ACTION)

Herbicides are also categorized by HOW they kill plants. This is called the “Mode of Action” Group.
Different groups attack different systems inside the plant.

A few common examples:
• Group 4 — Growth Regulators (Examples: 2,4-D, Triclopyr, Dicamba, Aminopyralid)

These mimic plant hormones and cause the plant cells to grow rapidly until the plant dies. This effect primarily occurs in dicot plants (broadleaf species) and not in monocots (grasses).

• Group 2 — ALS Inhibitors (Examples: Metsulfuron, Chlorsulfuron, Imazimox)

These stop the plant from producing certain amino acids it needs to grow. The plant slowly shuts down. Group 2 herbicides primarily affect broadleaf plants because broadleaf species are generally more sensitive to this enzyme pathway, while grasses can metabolize or tolerate these compounds more effectively in many cases. This makes them commonly used for selective broadleaf control in grass crops and rangelands.

• Group 9 — EPSP Inhibitors (Example: Glyphosate)

These block production of critical proteins the plant needs to survive. Because they work in most plants, they are considered non-selective.

PRE-EMERGENT vs. POST-EMERGENT

Another key distinction is timing:

• Pre-emergent herbicides (Example: Rejuvra/Indaziflam): Applied to soil before w**ds germinate. They create a barrier in the soil that stops seeds from germinating.

• Post-emergent herbicides (Examples: 2,4-D, Glyphosate, Dicamba): Applied after w**ds have already emerged and are actively growing.

A QUICK NOTE ON “NATURAL” OR HOMEMADE W**D SPRAYS

Homemade vinegar/salt/dish soap mixes are often promoted online as “safe” alternatives to herbicides. In reality, these mixtures can still damage soil, water, desirable plants, concrete, and metal surfaces — and some can cause skin or eye irritation.

Homemade w**d spray recipes also do not go through EPA registration, toxicology review, environmental testing, application research, or labeled rate development like registered herbicides do.

It is also very easy to overapply homemade salt/vinegar mixtures, which can unintentionally sterilize soil and damage surrounding vegetation for extended periods of time.

Ironically, some of these so-called "safer" homemade treatments that are concentrated vinegar/salt-based products can be much more corrosive and hazardous to handle than registered herbicides, especially when misused or overapplied.

This is not about “chemical vs. non-chemical.” EVERYTHING involved is a chemical, even the water the herbicides are mixed with. The distinction is whether a product has been evaluated, labeled, and tested for safe and effective use under specific conditions.

Registered herbicides are required to meet those standards. Homemade mixtures are not.

I used AI to make a graphic attached to this post, to simplify all the information written above. Feel free to save it for your reference.

Perennial Plant sale is now on at the Ravalli County W**d District. Replace your w**ds with beautiful plants. Gallon pot...
05/13/2026

Perennial Plant sale is now on at the Ravalli County W**d District. Replace your w**ds with beautiful plants. Gallon potted perennials only $5. We have a few herbs as well. Come on down and load up. Mon-Thurs 9-5. 121 south Tudor Street Victor.

Do you like to be outside working? We are hiring, looking for individuals to help us protect our landscapes for wildlife...
04/20/2026

Do you like to be outside working? We are hiring, looking for individuals to help us protect our landscapes for wildlife and future generations. Apply here: https://ravalli.bamboohr.com/careers
Monday thru thursday 10 hour days so you can enjoy your weekends.

We are hiring awesome people! Are you looking for a job that gets you out of an office setting? Please go to this link f...
03/30/2026

We are hiring awesome people! Are you looking for a job that gets you out of an office setting? Please go to this link for more information. https://ravalli.bamboohr.com/jobs/
We need sprayers and a pollinator/bio garden leader

Take a look at the current openings at Ravalli County

03/25/2026
Drop off your unwanted sellable items at 121 south Tudor street Victor or call 406-777-5842
03/02/2026

Drop off your unwanted sellable items at 121 south Tudor street Victor or call 406-777-5842

12/16/2025

So many of you have purchased flowers from us in the past. Just wanting to know if there is something different you would like to see or more of something or just some general ideas. Thanks for all your support.

We have Sun Chokes/Jerusalem artichokes harvested and ready to plant. $5 for 10 tubers. See us at the Ravalli County W**...
12/15/2025

We have Sun Chokes/Jerusalem artichokes harvested and ready to plant. $5 for 10 tubers. See us at the Ravalli County W**d District

The Ravalli County W**d District just listed this plant on our county w**d list.  It's one of those plants that is sprea...
11/25/2025

The Ravalli County W**d District just listed this plant on our county w**d list. It's one of those plants that is spreading pretty quickly and is a concern. Let us know if you need ideas on how to control it.

As we look towards the east for new invaders, South Dakota has many of the same w**ds as Montana, but they do list chicory as a noxious w**d. While chicory is known as a caffeine-free alternative to coffee, it is a plant that can also become invasive. Be careful that you don't plant this intentionally in your flower beds or landscaping because, while beautiful, it spreads very easily.

Chicory is an opportunistic plant that thrives in disturbed areas with thin grass, such as roadsides, pastures, fields, and lawns. It competes with native plants and desirable turfgrass, which can reduce biodiversity. It has a deep taproot that can allow it to regrow after being cut or mowed, and it can cause issues in dairy products if cows consume it, leading to a bitter taste.

To identify chicory, look for its bright blue or lavender flowers with toothed petals that typically bloom on sunny days, a zig-zagging stem, and basal leaves that resemble dandelion leaves. The plant can reach up to 5 feet tall and has a milky sap that oozes from broken stems or roots.

Address

121 South Tudor Street
Victor, MT
59875

Opening Hours

Monday 7am - 5pm
Tuesday 7am - 5pm
Wednesday 7am - 5pm
Thursday 7am - 5pm

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