Single Record

Participant Info

Species
Sonchus arvensis [Sonchus uliginosus] [Sonchus arvensis var. arvensis] [Sonchus arvensis var. uliginosus]
Family
Asteraceae
CommonName
perennial sow thistle
Presence
YES
Status
exotic, noxious
EarliestDate
1957
LatestDate
2016
Ecosystem
basin, shrubland, foothill, ruderal, urban
Geobotanical
Garitas, SSanjuans, NCristos, UBasin
Counties
Alamosa, Costilla, Rio Grande, Saguache
Passes
WildlifePreserves
Baca, Blanca Wetlands, Monte Vista, Russell Lakes
Other Localities
Del Norte
Comments
A relatively recent advent to the Valley, field sow thistle so far is present only in the Upper Basin and contingent foothills. The 2016 Del Norte photorecord of Sonchus arvensis var. uliginosus was within the town limits. There are, all told, fewer than 20 collections of S. arvensis, which still makes it the most commonly collected sow thistle in the Watershed. Judging from the USA distribution, which does not include the deep South, this species of Sonchus may be the most tolerant of colder climates. This exotic is on Colorado's C list of "noxious weeds." Our varieties include var. uliginosus and arvensis. Some authorities give them specific status (e.g., Ackerfield 2022). S. arvensis has been collected from the length of the Rio Grande drainage in New Mexico, but not farther down stream.