Foxtail Grass: How to Identify It, Why It’s Dangerous, and How to Control It

Foxtail grass may look harmless, but its sharp, barbed seed heads can seriously injure pets and animals. Learn how to spot it early and prevent it from spreading.

Weed Identification • Pet Safety • Lawn Care • Seasonal Weeds

Green foxtail is a common roadside grass and conspicuous only by mid to late summer.

Overview

Foxtail grass is a common name for several grass species, mainly within the Alopecurus and Setaria genera. These grasses are known for their dense, brush-like seed heads that resemble a fox’s tail—hence the name.

While foxtail can grow in many outdoor areas and blend into normal grass, it becomes a major hazard when seed heads dry out and break apart.

Characteristics

1) Common Types

In the United States, the most common foxtail types include:

  • Giant foxtail

  • Green foxtail

  • Yellow foxtail

2) Life Cycle

Most foxtails are summer annual weeds, meaning they:

 

  • Grow from seed in spring

  • Mature during summer

  • Die off in fall
    …but leave seeds behind for the next season.

3) Habitat

Foxtail is highly adaptable and commonly found in:

 

  • Lawns

  • Pastures

  • Roadsides

  • Fields

  • Disturbed or patchy soil areas

4) Identification Tips

The easiest way to identify foxtail is by its seed head.

Different foxtail species can be recognized by:

  • Hairs on the leaf surface

  • Color of the bristles

  • Whether the seed head stands upright or droops

Impact and Hazards

Why Foxtail Grass Is Dangerous

Foxtail grasses can be a serious threat to animals, especially when dry. Their seed heads contain sharp, barbed bristles called awns, which can attach to fur and skin easily.

Common Injuries Caused by Foxtails

Foxtail awns can:

  • Lodge in a pet’s mouth, nose, eyes, or ears

  • Get stuck between toes or in fur

  • Work deeper into tissue, causing pain and infection

  • Lead to abscesses and severe internal damage if they migrate into the body (including lungs or spine)

Because of their barbed design, foxtails are difficult to remove and do not back out naturally.

Management & Control

Mowing (Prevention Strategy)

Mow regularly to reduce foxtail growth.
Recommended height: 3–4 inches
Important: Mow before seed heads appear to prevent spread.

Hand Pulling (Best for Early Growth)

Remove foxtail plants while they are still young—before they develop seed heads in late spring or summer.

Mulching (Garden Bed Protection)

Apply 3–4 inches of mulch in garden beds to block sunlight and reduce germination.

Healthy Lawn Care

A thick, healthy lawn helps prevent foxtail from establishing. Focus on:

 

  • Proper fertilization

  • Reseeding bare patches

  • Consistent lawn maintenance

Water Management

Avoid excessive watering. Overwatering encourages foxtail growth and makes it easier for the weed to spread.

Quick Prevention Tips (Optional Section)

To keep foxtail from becoming a yearly problem:

  • Check lawns and walkways in spring

  • Remove foxtails before seed heads form

  • Keep grass thick and trimmed

  • Inspect pets after outdoor walks

  • Avoid letting foxtail dry out and scatter seeds

Foxtail grass is a common weed that can quickly become a serious hazard—especially for pets and livestock. Early detection, proper mowing, and healthy lawn habits are the best ways to control foxtail before it spreads and causes injury.