Tree of heaven

Discuss this plant with the guide — choose this profile as a possible match and prepare your observations for Colorado Plants & Practical Care.

Ailanthus altissima

Colorado noxious weed · List C — Manage widespread weeds. CO-rules-2025

Widespread and well established. Control is recommended by the state; local governments may require management. This is a management category, separate from danger ratings. Category source · What the lists mean.

Root suckers form persistent thickets. Exposure help.

Identification caveat: Distinguish from sumacs and walnuts using leaflet bases and other features. Established root systems require a coordinated control plan.

Still researching this plant

This is a sourced working profile. Evidence is incomplete for People, Dogs & cats, Other animals. Identification and source-photo limits are explained below. Independent botanical and veterinary review is pending. Uncertainty is not a finding that the plant is safe.

Three views of this plant

Source-identified reference photographs; these are not a complete identification key. A source location outside Colorado does not establish local occurrence.

Ailanthus altissima: Mature tree with a broad rounded leafy crown and single trunk. — **habit** — Mature tree with a broad rounded leafy crown and single trunk.
Darkone · CC BY-SA 2.5
Photo source and identification
Original record · Original image
Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination.
Wikimedia server-resized derivative; no crop, color change, or generative editing. Gallery display preserves the full image; the catalog preview uses a CSS crop.

Ailanthus altissima: Long pinnately compound leaves with many paired green leaflets. — **foliage** — Long pinnately compound leaves with many paired green leaflets.
Karduelis · Public domain
Photo source and identification
Original record · Original image
Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination.
Wikimedia server-resized derivative; no crop, color change, or generative editing. Gallery display preserves the full image; the catalog preview uses a CSS crop.

Ailanthus altissima: Four dry elongated winged fruits, each with a central seed, photographed with a scale. — **samaras** — Four dry elongated winged fruits, each with a central seed, photographed with a scale.
Steve Hurst @ USDA-NRCS PLANTS Database · Public domain
Photo source and identification
Original record · Original image
Source page scientific identification plus visual morphology review of the selected photograph. This is a source-identified reference image, not a specimen-based taxonomic determination.
Wikimedia server-resized derivative; no crop, color change, or generative editing. Gallery display preserves the full image; the catalog preview uses a CSS crop.

Recognize

Large compound leaves have leaflets with glandular teeth near their bases; fruits are elongated, winged samaras. N-ailanthus-altissima

Plants & habitat

Seeds and suckers form dense thickets that displace vegetation. It is a host for spotted lanternfly; tree presence does not prove that insect is locally present. N-ailanthus-altissima

People

The reviewed sources do not establish species-specific ingestion effects or a safe exposure amount for people. Missing evidence does not establish safety.

Dogs & cats

The reviewed sources do not establish species-specific ingestion effects or a safe exposure amount for dogs or cats. Missing evidence does not establish safety.

Other animals

The reviewed sources do not establish species-specific ingestion effects or a safe exposure amount for livestock. Missing evidence does not establish safety.

Before taking action

Confirm identification and the requirements of your county weed program. For chemical treatment, follow the current product label, including restrictions around animals and water. S27

References

CO-rules-2025 — Colorado Noxious Weed Act rules, 8 CCR 1206-2, Colorado Secretary of State / Department of Agriculture. Accessed 2026-09-07T01:07:48+00:00. Locator: Parts 3.1, 4.1, 5.1; management provisions; effective May 15, 2025.
N-ailanthus-altissima — ailanthus altissima — Plant Toolbox, NC State Extension. Accessed 2026-09-07T01:04:55+00:00. Locator: Description; Attributes; Problems; Poisonous to Humans.
S27 — 2103 – Colorado Noxious Weeds, PlantTalk Colorado · CSU Extension. Accessed 2026-09-07T00:23:57+00:00. Locator: List A, B and C management categories.

Content revised 2026-09-07 03:50:00Z · Source checks dated separately in the references.