Clonal Plants descended from a Captive/Cultivated

Simple question, complex answer: Does a plant that spreads clonally and is possibly still attached by root to its planted parent count as captive/cultivated. eg https://www.inaturalist.org/observations/155201325

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I think that cultivated plants that have spread vegetatively/clonally should be marked as cultivated if you’re reasonably certain that they are indeed the same individual. However, given that the population in the observation you referenced was planted about 100 years ago, it normally isn’t possible to know whether the original individual has died and been replaced by a sexually propagated descendent. As the final twist in this particular scenario, since Neviusia alabamensis has almost never ben observed setting seed, it seems pretty likely that this is the original planted individual and thus should be marked as cultivated.

One side note: I think observations like this are extremely valuable, and that marking an observation as “cultivated” should not move it to “casual.” That’s been a contentious matter for some time and I don’t expect it to be resolved anytime soon. As a researcher, I use observations of cultivated plants in several projects, so don’t despair, someone might use your observation for research even if it’s marked as cultivated.

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I think that there comes a time in a plant’s clonal spread when we should simply treat it as wild, even if it got to the site originally because it was planted. Asexual reproduction has happened. Example: this Yellow Archangel ( https://www.inaturalist.org/observations/97110638 ) was apparently planted at this site long ago, next to a trellis, but it has spread into the surrounding woods. Wild. Certainly. I don’t think we need to dig it up to figure out whether the entire clone is still attached or not, though with this plant probably parts are no longer attached.

My colleagues and I debate this regarding the quasi-wild rhizomatous bamboo we’re investigating in the Pacific Northwest. None of these came up from seed. A few were transported by floods or by earth-moving equipment (wild). Most, however, are spreading by rhizomes from where they were planted. Which should we treat as wild? Obviously not the ones still in the garden where they were planted. What about the ones that have run under the fence and are spreading next door? (Depends.) What about old, untended stands that have been slowly spreading for decades, since before the house formerly nearby was destroyed and utterly obliterated? (Wild for us, so marked wild on iNaturalist, though with some mental reservations.) And does it matter if landowners and neighbors are mowing or otherwise trying to control/kill parts of the spreading bamboo?

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And does it matter if landowners and neighbors are mowing or otherwise trying to control/kill parts of the spreading bamboo?

I know of at least one bamboo like this nearby me. They grew it in their garden for years. At some point it got removed from that garden, but where the root that spread out got left it’s still trying to punch through the public pavement a few feet away from where it used to be. I’d call that little scrap wild but I can see why someone wouldn’t - oh, and I reckon it’ll spread back to the garden where it came in a few years time…!

Some things are quite clearly wild when they do this; every Japanese knotweed in the UK is genetically identical. It’s usually spread by fragments of root getting stuck to tools or bits being lifted and carried away by water (probably why almost all the plants I know of are on riverbanks). They seem quite wild to me!

With attached stuff the rule of thumb I use is “if the original plant was cut down and stump-ground into nothing, would this descendent die?” For me at least it’s hard to argue this Tree of Heaven pushing up the pavement many years after the “original” tree was cut down is ‘cultivated’. I don’t think I could say the same of this Prunus. That’s not spreading, that’s a basal sucker with an ego!

I think “always no” would risk losing good data too; much like the Variegated Yellow Archangel (hey, that’s an invasive here too, in the same way!) above, here there are quite a few invasives here that mostly or only spread only by their roots. Winter heliotrope Petasites pyrenaicus cannot set seed here since all of the ones found here are male - it spreads exclusively by, waste dumping, dislodged roots, or spreading beneath the ground. So, this group nowhere near water probably came from one of the houses nearby (or maybe garden waste dumps) - either way it is now self-sustaining. If there was an original plant, it would hardly notice if that was gone, it’d carry on spreading along the path, displacing other things as it went.

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I wouldn’t hesitate to call the plant cultivated.

It’s not the same situation, but it’s arguable that uploading dozens of creosote or aspen photos in close proximity (at least 1 user in my region does often) is a form of duplicate observations of clonal organisms.

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Why not review the numerous threads where different variations on the same question have been discussed to death?

Maybe. And maybe not. Years ago I was involved in a genetic study of aspen clones that revealed that sometimes a clone is one individual and but often it’s two or more individuals growing together.

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This is a very good question because this is a case that can frequently occur and applies to a certain number of ornamental species that are potentially very invasive. Think about Acacia, Populus and bad company.
If left unmanaged, they tend to produce suckers from the rhizome.
So, when to think that they have become wild? As often, I think that it is a matter of common sense and usefulness. Maybe a criterion could be if the suckers and the new stems have succeeded in invading a nearby natural habitat. On the contrary, if a poplar planted in an urban park has produced some new stems few meters from the main plant, I would still consider it as cultivated.
A couple of cases:
Petasites pyrenaicus that was originally planted without any doubts but now has covered an area of some tens of square meters:

Acacia dealbata that, starting from an individual cultivated in a private property, has spread and formed a maquis in the nearby Pinus maritimus wood:


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Normally I will ask myself:

  1. Does the individual organism (not the previous generations) requires intentional human effort to appear here?
  2. Is it receiving intentional human effort to survive?
  3. Does it require intentional human effort to reproduce?
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How about this? When the plant has spread beyond the area where it is or was being cultivated and the clones are capable of living on their own if there was no connection to the original plant, then it is to treat it as a new, wild individual. Even if the connection to the original has not been severed.

This would also cover the case of the aspens. If someone makes two separate observations of what appears to be two aspen trees is one a duplicate of the other?

If you don’t accept that definition, what about the coast redwood? When the tree dies and we get the fairy ring of clones, are those all considered one and the same or can they be treated as separate.

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