Will Crossbow Kill Grass

If you’re dealing with tough weeds in your lawn, you might be wondering, will crossbow kill grass? The short answer is yes, it absolutely can. Crossbow Herbicide is a powerful, broadleaf weed killer that’s also deadly to unwanted vegetation, including many types of grass, especially if they are not established, mature turf. This makes it a fantastic tool for clearing areas but a risky one for spot-treating weeds in a lawn you want to keep.

Understanding how Crossbow works is key to using it safely and effectively. This guide will walk you through everything you need to know, from its ingredients to step-by-step application, so you can get the results you want without accidentally harming your desirable plants.

Crossbow is specifically formulated to control woody plants, brush, and broadleaf weeds. Its two active ingredients are 2,4-D and triclopyr. These are systemic herbicides, meaning they are absorbed by the leaves and then move throughout the entire plant, killing it from the roots up.

While it’s excellent against broadleaf invaders, many grasses are susceptible to triclopyr. Young, newly seeded, or stressed grasses are particularly vulnerable. Established, healthy cool-season turfgrasses like Kentucky bluegrass or tall fescue have some tolerance, but application must be precise. Warm-season grasses like Bermudagrass or Zoysia are more sensitive. Essentially, if you spray Crossbow carelessly, you will likely see yellowing or death of grass in the treated area.

What Exactly is Crossbow Herbicide?

Crossbow is a post-emergent herbicide, meaning it kills plants that are already growing. It’s not a pre-emergent that stops seeds from sprouting. It’s known for its effectiveness on hard-to-kill perennials like poison ivy, blackberry, and kudzu. People often turn to it when standard lawn weed killers fail.

2,4-D: Targets a wide range of common broadleaf weeds like dandelions and clover.
Triclopyr: Adds power against woody plants, vines, and tougher broadleaf weeds. It’s also the component that can injure or kill grasses.

When Using Crossbow Will Kill Your Grass

There are specific situations where grass death is the goal or a likely outcome. Knowing these helps you avoid accidents.

Total Vegetation Clearance: For preparing a garden bed, clearing a fence line, or reclaiming an area from brush, Crossbow is a great choice to kill everything.
Overspray or Drift: On a windy day, fine herbicide droplets can drift onto your lawn. Even a small amount can cause damage.
Over-application: Using too high a concentration or spraying the same area multiple times will overwhelm grass tolerance.
Treating Stressed Grass: Applying during drought, extreme heat, or right after mowing puts extra stress on turf, making it more susceptible to injury.

How to Minimize Grass Damage When Using Crossbow

If you need to use Crossbow near a lawn you want to preserve, extreme caution is needed. Follow these steps to protect your grass.

1. Choose the Right Tool for the Job

Never use a broadcast sprayer. Instead, use a handheld pump sprayer with a adjustable nozzle that allows for a precise stream or a shield to prevent overspray. For very small patches, a sponge applicator or even a small paintbrush lets you wipe the herbicide directly onto the weed leaves.

2. Mix and Apply with Precision

Always follow the label instructions for the specific weed you’re targeting. Do not exceed the recommended concentration. Here is a general process:

Fill your sprayer with the required amount of water first.
Add the measured amount of Crossbow concentrate.
Secure the lid and shake thoroughly to mix.
Set the nozzle to a coarse, low-pressure stream to minimize misting.
Spray only on a calm, cool day with no rain forecast for 24 hours.
Hold the sprayer close to the target weed and apply directly until the leaves are wet but not dripping.

3. Post-Application Care

After spraying, clearly mark the area if possible. Avoid watering the treated spot for at least 24 hours to allow full absorption. Do not mow the surrounding grass for a few days to prevent spreading the herbicide via clippings. Monitor the area for any signs of grass yellowing.

What to Do If You Accidentally Kill Grass

Mistakes happen. If you see brown patches appearing in your lawn after an application, act quickly.

Water Thoroughly: Immediately flood the area with water to dilute the herbicide in the soil. This can help limit further root uptake.
Remove Dead Turf: Once the grass is clearly dead, use a shovel or sod cutter to remove the damaged patch.
Prep the Soil: Loosen the exposed soil and add a thin layer of compost to improve conditions.
Re-seed or Re-sod: Replant with grass seed appropriate for your region, keeping it consistently moist until established. For faster repair, you can cut and fit a piece of new sod into the space.

Safer Alternatives for Lawn Weed Control

If your goal is to kill weeds like dandelions without harming your lawn, consider these alternatives before reaching for Crossbow.

Selective Lawn Weed Killers: Products containing only 2,4-D, Dicamba, or MCPP are formulated to target broadleaf weeds while leaving most grasses unharmed. These are your first line of defense.
Spot Treatment with Vinegar: For isolated weeds, horticultural vinegar (20-30% acetic acid) can be effective but requires careful application as it will kill any plant tissue it touches.
Manual Removal: Using a long-handled dandelion digger or a simple garden knife to remove the taproot is a chemical-free method that’s very effective for scattered weeds.
Maintain a Healthy Lawn: The best defense is a thick, vigorous lawn. Proper mowing, fertilization, and watering will crowd out many weeds naturally, reducing the need for herbicides altogether.

The Best Uses for Crossbow Herbicide

Given its strength, Crossbow shines in scenarios where its power is an asset, not a risk. Here are it’s ideal applications:

Clearing Overgrown Fields or Pastures: It’s excellent for managing brush encroachment in large areas.
Preparing Garden Beds: To kill all existing vegetation before starting a new flower or vegetable garden.
Fence Line and Roadside Maintenance: Controlling tough vines, brambles, and saplings along property borders.
Targeting Specific Problem Plants: Eradicating invasive species like poison ivy, wild blackberries, or tree saplings in landscape beds (using careful, directed application).

Frequently Asked Questions (FAQ)

How long does it take for Crossbow to kill grass?

You will typically see wilting and yellowing within 1-2 weeks, with complete kill taking up to 3-4 weeks, depending on the grass type and growing conditions.

Is Crossbow safe for all grass types?

No. It is not safe for most grasses when applied directly. Some established cool-season grasses may tolerate it at low rates, but it’s generally not recommended for use on lawns. Always check the product label for specific grass tolerances, which can vary.

Can I plant grass after using Crossbow?

Yes, but you must wait. The label typically recommends waiting 1-2 weeks after application before reseeding treated areas for broadleaf weeds, and longer (often 3-4 weeks) if you were targeting tough perennial vegetation. Always conduct a simple germination test in a small area first.

What is the difference between Crossbow and Roundup?

Roundup (glyphosate) is a non-selective herbicide that kills virtually all plants it contacts. Crossbow is selective for broadleaf plants and woody species but is more dangerous to grasses than standard lawn weed killers. Crossbow also tends to have longer soil residual activity for some plants compared to glyphosate.

How do I clean my sprayer after using Crossbow?

Proper cleaning is crucial to prevent damage to other plants. Triple-rinse the tank with clean water, running it through the hose and nozzle each time. Then, fill with water and add a tablespoon of household ammonia, agitate, and let sit for 15 minutes before a final rinse. This neutralizes any remaining herbicide residue.

Final Thoughts on Using Crossbow

Crossbow Herbicide is a highly effective solution for tough, unwanted vegetation. Its potent mix of 2,4-D and triclopyr makes it deadly to unwanted vegetation like brush, vines, and stubborn weeds. However, this same potency means it can also be deadly to your lawn grass if not used with utmost care.

The key takeaway is to match the tool to the task. For general lawn weed control, a standard selective herbicide is a safer, better choice. But for clearing land, managing brush, or eliminating perennial invaders where grass survival isn’t a concern, Crossbow is an invaluable tool. Always read and follow the label instructions—it’s the law and the best guide to successful, safe application. By understanding its strengths and limitations, you can harness it’s power without suffering unintended consequences in your garden.