Posted by SylvanNM • 3 weeks 2 days ago
A few sites in NM are observing cane cholla, Cylindropuntia imbricata. It is hard to determine when fruits are ripe. The guidance says fruits are yellow, but the fruits are seldom a solid yellow color and there isn't much information online about what fruits look like when they are ripe. There's even conflicting information about whether fruits ripen within one year or take longer. Eventually, sometimes after two years, a mostly yellow fruit will just turn tan colored and shriveled before falling off. The BioPark has a volunteer working on a phenology guide for this species for our area, but the fruit ripeness remains an open question. We've thought about dissecting some greenish-yellow fruits to see if the seeds seem mature.
We would appreciate any information or suggestions you can provide.
Hello SylvanNM,
Thanks for reaching out! Cylindropuntia species fruits can be tricky, especially because they have other ways to reproduce. We've received some other observer comments about this and I have been working on updated phenophase descriptions to help clear things up. Here is the updated "Ripe Fruits" description I have for Nature's Notebook:
"One or more ripe fruits are visible on the plant. For Cylindropuntia imbricata, a fruit is considered ripe when it has turned green-yellow or bright yellow and lost its spines."
Like you mentioned, color is not so great of an indicator. Fruits can sometimes appear very yellow and fade back to a greener color over time on the plant. A quality of mature fruits I have found in many sources about the species (primarily Donald J. Pinkava's description in Flora of North America) is the loss of spines. This is what I would recommend to look for instead of color alone. To my knowledge, spines will not grow back on a fruit, so it should be clear when they have passed the threshold into ripeness.
I hope this information is helpful. Please share any insights when you complete the phenology guide or if you dissect any fruits. Feel free to reach out with any further questions.
Happy observing!
Oskar
Plant Specialist, USA-NPN
[email protected]