Common ragweed (Ambrosia artemisiifolia) is a widespread and troublesome weed that causes problems for farmers, gardeners, and land managers. It grows quickly, spreads easily, and produces large amounts of pollen that can cause allergies.
Getting rid of ragweed is not simple. The best way to control it depends on where it is growing.
In fields with crops like corn or soybeans, different herbicides are used before or after the weed starts growing.
In pastures and lawns, selective herbicides and good maintenance are key to protecting grass and forage while killing the weed.
Each area requires a specific plan, as the same methods don’t work everywhere.
This article explores the herbicide strategies that work best in different environments, from row crops to residential lawns.
By understanding which products and methods to use in each situation, you can develop a more effective plan for controlling ragweed and protecting your plants.
| Aspect | Soybean Crops | Cornfields | Lawns | Pastures |
|---|---|---|---|---|
| Goal | Eliminate ragweed while protecting soybean plants, ensuring maximum yield. | Eliminate ragweed while protecting corn plants, maximizing crop yield. | Eliminate ragweed while preserving turfgrass. | Eliminate ragweed while preserving forage plants for grazing livestock. |
| Herbicides Used | Glyphosate, dicamba, 2,4-D (specific for herbicide-tolerant soybeans). | Broad-spectrum herbicides like atrazine, dicamba, and Status. | Selective broadleaf herbicides like 2,4-D, dicamba, and MCPP. | Broadleaf herbicides like 2,4-D, Grazon, Crossbow, or Milestone. |
| Herbicide Type | Both PRE (Preemergence) and POST (Postemergence) products. | Both PRE (Preemergence) and POST (Postemergence) products. | Primarily POST (Postemergence) products for spot or broadcast applications. | Mostly POST (Postemergence) products. |
| Crop/Turf Safety | Must avoid damaging sensitive soybean plants. | Corn is tolerant to certain herbicides like atrazine and dicamba. | Turf-safe herbicides to avoid harming grass species. | Herbicides must be selective to avoid harming forage grasses or legumes. |
| Resistance Concerns | ALS- and glyphosate-resistant ragweed populations are a major challenge in soybeans. | Resistance concerns are lower with atrazine-based products but still present for ALS inhibitors. | Resistance is generally not a major concern in lawns. | Resistance concerns exist but are less critical than in row crops like soybeans or corn. |
Contents
Ragweed Control Strategies for Soybeans
Soybean crops have unique challenges, especially due to the widespread occurrence of ALS-resistant and glyphosate-resistant ragweed in many areas.
Management often involves integrated herbicide programs combining different modes of action.
Soybean management heavily relies on herbicide-tolerant traits (glyphosate, dicamba, or 2,4-D resistance).
Preemergence Herbicides
- Boundary (S-metolachlor + metribuzin): Provides broad-spectrum weed control.
- Authority or Valor products (sulfentrazone or flumioxazin): Effective for small-seeded broadleaf weeds like ragweed.
- Dual Magnum (S-metolachlor): Often used in tank mixes for residual control.
- Zidua (pyroxasulfone): Offers extended residual control for ragweed.
Postemergence Herbicides
Some of the herbicide options for herbicide-tolerant soybeans include:
- Glyphosate-tolerant soybeans (Roundup Ready): Use glyphosate for effective post-control, but avoid overuse due to resistance concerns.
- Dicamba-tolerant soybeans (Xtend): Use dicamba-based products like XtendiMax or Engenia.
- Enlist soybeans (2,4-D-tolerant): Use Enlist One (2,4-D) or tank mixes for ragweed control.
- Non-tolerant soybeans: Use combinations like Flexstar (fomesafen) or Basagran (bentazon) for broadleaf weeds.
Rotate herbicides with different modes of action to prevent resistance development. Example: use a preemergence herbicide with one mode of action (e.g., sulfentrazone) and follow it with a postemergence herbicide from another class (e.g., dicamba or fomesafen). Avoid using ALS-inhibiting herbicides (e.g., Pursuit, Raptor) alone if ALS resistance is present.
Ragweed Control Strategies for Corn Crops
Effective ragweed control in corn requires a strategic approach combining preemergence and postemergence herbicides.
Preemergence herbicides help prevent ragweed from germinating and growing early in the season, while postemergence herbicides target any plants that emerge later.
Choosing the right combination of herbicides ensures prolonged weed control without harming the crop.
Effective preemergence herbicides
Products containing atrazine combined with one of these:
- Hornet
- Balance
- Balance Flex
- Corvus
- Callisto
- SureStart
- Lumax
- Lexar
Regional Restriction: Balance, Balance Flex, and Corvus are not approved for use in Michigan, Minnesota, and Wisconsin.
Adding extra atrazine improves ragweed control but must follow the maximum allowable rates based on soil type.
Atrazine Alone:
Atrazine or atrazine-containing products can work alone if applied at 1.5 lbs. ai/A (active ingredient per acre) or higher.
Effective postemergence herbicides
Some of the postemergence herbicides you can apply for ragweed control in cornfields, following a preemergence application, include:
- dicamba
- Status
- 2,4-D amine
- Hornet
- Stinger
- WideMatch
- Atrazine with Buctril, Callisto, Impact, Laudis
- Northstar
- Yukon
- Beacon or Spirit (not in ALS-resistant populations)
If no preemergence application was used before, you can apply the following herbicides in your postemergence treatment.
- Glyphosate plus atrazine or an atrazine premix product (in Roundup Ready corn only).
- Glyphosate plus either Lexar or Lumax (in Roundup Ready corn only).
- Ignite plus atrazine or an atrazine premix product (in Liberty Link corn only).
- Lightning plus atrazine (in Clearfield corn only).
- Steadfast ATZ plus one of the following: Callisto, Impact, or Laudis.
- Atrazine plus either Hornet or SureStart.
Ragweed Control Strategies for Lawn
Ragweed control in lawns is different, as lawn management emphasizes preserving desirable grass while selectively targeting ragweed and other broadleaf weeds.
Selective herbicides are crucial in lawns to ensure the grass remains unharmed.
Common products include those with active ingredients like 2,4-D, dicamba, or MCPP, which are available in consumer-friendly formulations such as Weed-B-Gon or Trimec.
Other selective herbicide for controlling this weed are:
- Tenacity (mesotrione)
- Trimec (2,4-D, dicamba, and MCPP)
- Weed-B-Gon (2,4-D, dicamba, and MCPP)
- Spectracide (2,4-D, dicamba, and MCPP)
- Crossbow (2,4-D, triclopyr)
- Celsius WG (dicamba)
- Ferti-Lome Weed-Out (2,4 D, dicamba, and MCPP)
- Gordons SpeedZone(2,4-D, dicamba, and carfentrazone.)
Ragweed Control Strategies for Pasture
Unlike corn and soybean fields, where the focus is on maximizing crop yields, or lawns, where the goal is to maintain healthy turfgrass, pasture management must prioritize both weed control and the preservation of forage plants for grazing livestock.
Additionally, herbicides used in pastures must be safe for animals, often requiring specific grazing restrictions.
Selective herbicides are key to managing ragweed in pastures, as they target broadleaf weeds without damaging desirable forage grasses.
- 2,4-D
- Grazon: A combination of picloram and 2,4-D, widely used in pastures.
- Crossbow: A mix of 2,4-D and triclopyr, good for woody and broadleaf weeds.
- Milestone
- Tordon 22K
- ForeFront HL
- Surmount
- PastureGard HL
Always check the grazing restrictions on the herbicide label to ensure livestock safety.
My name is Dani and I am a farmer with 15 years of experience. I will share with you everything about farming from processes, tips, machines, and more. Farming for me is not just a job but a way of life. Keep reading ...
