Sedum of North America: Sedum ternatum vs. Sedum sarmentosum

I've decided to start writing a few identification guides for those who might be interested in ID'ing Sedum.

Sedum ternatum is a common native Sedum that is primarily found in the east coast of North America. It is most common in rocky outcrops or forest floors. In forested areas, it tends to grow in moister areas. It can spread through underground rhizome.

Sedum sarmentosum, on the other hand, is native to East Asia and Southeast Asia. It has been introduced to much of America, and due to its vigorous growth, is becoming more and more common.

Both species grow leaves in whorls of 3, and both have basal rosettes/buds.

Below is a general guide on differentiating the two.
Sedum ternatum:

• Leaves are rounded and wide, almost like a circle or teardrop
• Dark/medium green
• Blooms are white
• Generally blooms in spring
• Grows in upright rosettes

• Basal rosettes can stress red/pink from cold stress
  Emerging from basal rosettes: https://www.inaturalist.org/observations/161721051
  Flowers and full plant: https://www.inaturalist.org/observations/75935355

Please do note -- there is a species of Sedum that looks quite similar in dormant stages (Sedum pulchellum). Maybe I'll write a guide for differentiating these two in the future.

Sedum sarmentosum:

• Leaves are skinny and pointed at one end... like a skinny diamond
• Light lime green (Sometimes yellow, or light green)
• Blooms are yellow
• Generally blooms in the summer
• If not in dormant buds, S. sarmentosum can grow in elongated, trailing stems.

• Dormant buds rarely fully turn red when cold stressed
  Emerging from dormant buds: https://www.inaturalist.org/observations/158605614
  Blooms: https://www.inaturalist.org/observations/161577501

Lastly, note that there is a look-alike plant to S. sarmentosum: Nuttallanthus canadensis
It can be diffrentiated from S. sarmentosum through the growth pattern. One feature may be how numerous stems sprout out of a compact center. Another feature may be the difference in which the growths look compared to the shape of s. sarmentosum emerging from dormant buds. The best way would be to get photos of the flowers, as the floweres of N. canadensis are very different than that of any Sedum.
Emerging growth: https://www.inaturalist.org/observations/152078185

Hope this helps
Picklejar

Posted on May 17, 2023 02:42 PM by picklejar