Also known as: Eggleaf spurge, Balkan spurge
Oblong spurge is often planted in gardens – with brilliantly bright yellow flowers, it’s no wonder why! However, it doesn’t remain an ornamental for long. Its seed capsules can eject seeds up to six feet away! Once established, it spreads quickly through natural areas and along waterways.
CAUTION: Avoid handling this plant! Its stems contain a milky sap that irritates skin.
For a more detailed description, download the Oblong Spurge Best Management Practices factsheet.
Description:
| Life Cycle: | Perennial (life cycle lasts more than one year) |
| Early Detection and Rapid Response species: | Yes |
| Height: | 3 feet (1 meter) |
| Leaf Description: | Light green, oblong leaves have finely toothed edges. They grow alternate along the stem. Its leaves and stems contain a milky, latex sap that can cause skin irritation. This sap is toxic to humans and livestock when touched or consumed. |
| Fruit & Flower Description: | Small, yellow flowers grow in clusters surrounded by yellow-green bractsBracts Leaf-like structures below a plant’s flower.. Three brown seeds are contained in oval seed pods. Once the seed pods ripen, the seeds are ejected several feet away. |
| Bloom Time: | March to August |
How it spreads:
- Water currents carry ejected seeds downstream along streams and rivers.
- Its seed’s sticky coating allows them to easily stick to boots, cars, clothing, equipment, and animals’ fur.
- Fragmented roots can also generate new plants.
Habitat:
- This hardy species grows in a variety of habitats. It prefers moist soils along streams, in wet meadows, and shady woodlands. It can also be found in yards and gardens.
- Prefers partial shade to full sun.
Impact:
- Its toxic sap causes skin and eye irritation if handled without proper protection. It can also cause internal soft tissue issues in livestock if consumed.
- Because of its toxicity, it offers little resources to wildlife. It only displaces native plants that wildlife use for food and habitat.
- It forms dense stands that create a monocultureMonoculture A single crop or plant species in an area., outcompeting native plant species.
What we’re doing about it:
- Oblong spurge is a priority species for the Tualatin SWCD. As such, our Invasive Species Program has been actively monitoring and treating it throughout the watershed.
- If identified within Washington County, a specially trained crew can come out and survey for it. If found, the crew will treat the infestation for free.
What you can do about it:
- Please report any oblong spurge infestations to the Oregon Invasive Species Hotline.
- Manual: Do not mow oblong spurge as this will only spread it to new locations.
- Hand pulling small patches can be effective. Spring is the best time to remove it—when the soil is damp and before it has gone to seed. Make sure to wear gloves whenever handling oblong spurge.
- Make sure to remove the entire root system and throw away the plant in a plastic bag in the trash— not your yard waste bin or home compost.
Look-alikes:
Leafy spurge (Euphorbia esula), another invasive species, looks similar to oblong spurge. Leafy spurge’s leaves are longer and thinner than oblong spurge’s leaves.
Noxious Weed Listing:
| State of Oregon: | Class A |
| State of Washington: | Class A |
More Resources:
- Pacific Northwest Weed Management Handbook: Oblong or eggleaf spurge
- University of California, Weed Research & Information Center: Oblong spurge