Poison Hemlock Control in Southwest Colorado

Deadly Toxic. Fast Spreading. Expert Removal Services for Your Safety

Poison hemlock (Conium maculatum) is one of the most dangerous invasive plants in Colorado. Just a small amount can be fatal to humans and animals if ingested. It spreads aggressively in pastures, ditches, wetlands, and disturbed soils—and proper removal is crucial. At Durango Animal Removal and Pest Control, we use careful identification, safe removal methods, and strategic treatments to eliminate poison hemlock while protecting your land and health.

Why Poison Hemlock is a Serious Threat

  • Toxicity: All parts of the plant are highly poisonous—especially unripe seeds and leaves. Exposure can cause respiratory paralysis and death in humans and livestock.
  • Misidentification: Often mistaken for wild carrot, parsley, or sweet cicely. Correct identification is critical for safe control.
  • Spread: A single plant can produce thousands of seeds. It rapidly colonizes streambanks, roadside ditches, vacant lots, and moist areas.

According to the WA State Noxious Weed Control Board, poison hemlock is a Class B noxious weed that is aggressively invasive, toxic even when dried, and impossible to safely compost. Our removal plans follow safety guidelines used by restoration ecologists and tribal land managers.

Identification Tips

  • Height: 6–10 feet tall in second year of growth.
  • Leaves: Lacy, fern-like, with a strong musky odor when crushed.
  • Stems: Hairless, hollow, with purple blotches—one of the most distinctive identifiers.
  • Flowers: Small white flowers in umbrella-shaped clusters in late spring.
  • Lookalikes: Wild carrot (Queen Anne's lace) has green, hairy stems and blooms in late summer. Poison hemlock stems are smooth and purple-spotted.

Safe and Effective Hemlock Control Methods

1. Manual Removal (for small infestations)

  • Wear gloves, long sleeves, and a face mask—sap is toxic on contact.
  • Use a shovel or mattock to dig the entire root system before the plant flowers (typically March to May).
  • Do not mow or weed-whack—it can aerosolize toxins and encourage regrowth.
  • Bag all removed plant material in sealed black plastic. Do not compost—even dried plant material remains toxic.

2. Chemical Control (for large infestations)

  • Best applied in early spring to basal rosettes, or in late summer for regrowth.
  • Effective products include glyphosate, 2,4-D, triclopyr, or combinations designed for broadleaf control.
  • Use extreme caution near water bodies—follow label directions exactly.
  • Multiple treatments may be needed over 1–2 years to exhaust seed banks.

3. Follow-Up & Prevention

  • Monitor the site regularly for seedlings or resprouts.
  • Establish desirable grasses or native plants to crowd out invasive regrowth.
  • Do not till or disturb the soil, which can bring dormant seeds to the surface.

Water Hemlock vs. Poison Hemlock

Though often confused, water hemlock (Cicuta douglasii) is another deadly plant found in Southwest Colorado wetlands. Its roots are particularly toxic, and it prefers wetter soils than poison hemlock. Control methods are similar: mechanical removal with full PPE, sealed disposal, and repeated herbicide application as needed.

Service Area

We provide poison hemlock removal across Durango, Bayfield, Ignacio, Pagosa Springs, and all surrounding areas in La Plata, Archuleta, and Montezuma counties.

Sources & References:

Request Safe Removal Today

Don’t take chances with poison hemlock. Call Durango Animal Removal and Pest Control to schedule a safe inspection and removal plan. We are trained, licensed, and equipped to handle even large infestations near homes, livestock, and waterways.

  • ⚠️ Extremely Toxic to People and Animals
  • ✅ Safe Disposal and Herbicide Application
  • 📍 Locally Owned and Operated in SW Colorado

Let’s remove it before it spreads—or causes serious harm.