Auk wrote:

Winter wrote:

... the plant does not have a sensor for that.It is simply the physically limited space. There's no more room. It can't grow any further.

This is the part that does not convince me. The plant in the pot with good soil has still plenty of space to grow roots among the ones it already has. In fact if we would measure the volume of the roots in a pot and in nature I believe the tree in the pot would have more, but it still can't grow that large. I think they can somehow sense it, like they sense what's up and down, where's the sun, or the crawling plants sense the branches and so on. Of course, I'm just guessing.

I doubt pot-tropism is a thing.
Maybe they've evolved after thousands of years of being placed in containers by humans

Winter wrote:

the crawling plants sense the branches and so on. Of course, I'm just guessing.

Have you ever seen how a crawling plant grows and it winds itself around branches? It really does NOT have sensors. Actually, it doesn't even have any idea what it's doing. Look up a movie, you'll understand.

Auk wrote:

Winter wrote:

the crawling plants sense the branches and so on. Of course, I'm just guessing.

Have you ever seen how a crawling plant grows and it winds itself around branches? It really does NOT have sensors. Actually, it doesn't even have any idea what it's doing. Look up a movie, you'll understand.

I actually saw a documentary about it, and it says they can smell. They tested it in many ways and the only time the plant could not locate the branch was when they covered it in glas preventing the airflow/smell.

How do plants smell?
Kind of earthy.

Sorry.
Do you have a link to this documentary?

BonsaiLearner wrote:

How do plants smell?
Kind of earthy.

Sorry.
Do you have a link to this documentary?

I've seen it. It's a hypothesis. Plants do not have a nervous system to process smell, so they do not really smell.
Crawling plants wind themselves around plants simply by growing in a certain direction; they sort of spin around until they hit something. Same as when you'd swing a rope and it hits a pole. The rope will wind around that pole.

Seems certain plants have a preference for plants to climb in. That's what 's in the movie and in the experiment. Google 'plants can smell', it's easy to find.

I know there are plants that have (mechanical) sensors - I've had them: venus fly traps. Pretty amazing how these sensors work. The trap will not close if you simply touch it, you have to hit two at the same time,or the same one multiple times within a certain time period.

Plants can be clever... but they reallly do not have sensors to measure the amount of space in a pot.

BonsaiLearner wrote:

How do plants smell?
Kind of earthy.

Sorry.
Do you have a link to this documentary?

Here it is:


Check the first seconds of the video: The parasite plant does rotate, but not randomly - it rotates toward the host plant.

Auk wrote:

Winter wrote:

I think this is exactly it. It has all it needs and more in the canister, but it somehow feels that it has limited space and it stops growing. If only we could bypass this sensor ...

Let's try and not make up wild theories... the plant does not have a sensor for that.It is simply the physically limited space. There's no more room. It can't grow any further.

BonsaiLearner wrote:

I doubt pot-tropism is a thing.

Pff.. It is NOT a wild theory. It is a fact and has been described for decades in dozens of articles on the subject. I have not been able to find a single article that conclusively explains the exact mechanism. But restricting root-growth, restricts upper canopy growth.

treebag.com/research-article/root-restri...fabric-containers-2/
www.actahort.org/members/showpdf?booknrarnr=787_28
journal.ashspublications.org/content/125/1/143.full.pdf
cereals-2.ahdb.org.uk/publications/docum...nce_2002_paper_6.pdf
journal.ashspublications.org/content/119/6/1157.full.pdf
journal.ashspublications.org/content/117/3/362.full.pdf

leatherback wrote:

Auk wrote:

Winter wrote:

I agree LB. But apart from us not being able to find a proof for this, we can, let's say, find holes in the existing theories.

there is plenty of proof. There is no full explanation. A fully different thing.