Toxic invasive weed confirmed spreading in LA County
iNaturalist: chloroxiphite
Invasive Species
If you hike or garden near canyons and slopes in LA County, this fast-spreading weed can crowd out native plants and poison grazing animals if it shows up near pastures.
Someone spotted a plant called Crofton Weed in Los Angeles County and submitted a photo to iNaturalist, where other experts confirmed the identification, making it a verified sighting. This plant isn't native to California, it spreads aggressively, and it's actually toxic to horses and other grazing animals, so tracking exactly where it pops up helps land managers keep tabs on its spread.
Key Findings
Observation reached 'research-grade' status on iNaturalist, meaning the species ID was confirmed by community consensus
Location confirmed as Los Angeles County, US-CA, US
Ageratina adenophora is a known invasive species with documented toxicity to livestock, particularly horses
chevron_right Technical Summary
A citizen scientist confirmed Crofton Weed, an invasive plant toxic to livestock, growing in Los Angeles County, adding a verified data point to tracking how this weed spreads across California.
Abstract Preview
Original paper
Crofton Weed (Ageratina adenophora) observed in Los Angeles County, US-CA, US
Research-grade observation of Crofton Weed in Los Angeles County, US-CA, US.
open_in_new Read full abstractAbstract copyright held by the original publisher.
Species Mentioned
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Ageratina adenophora, commonly known as Crofton weed, is a species of flowering plant in the family Asteraceae native to Mexico. Originally grown as an ornamental plant, it has become invasive into farmland and bushland worldwide. It is toxic to horses, which develop a respiratory disease known a...