Well at least we know where you get your sources from. https://en.wikipedia.org/wiki/Tree

Since there isn't a technical or widely accepted scientific definition of the word "tree", its perfectly fine to call bamboo a tree.

Nope, Bamboo is a grass :)

Disclaimer: I'm a microbiologist, not a botanist, although I took a bunch of botany and mycology courses to fill my elective requirements and for.... recreational reasons.

There are a few cultivars, like double mahoi, that'll produce fruit twice before dying back, but 5-6 is unusual.

The usual cycle is a single "trunk" (pseudostem) will grow, flower, fruit, then die. As it grows, it'll produce daughter plants which appear as additional, initially smaller trunks which follow the same cycle, just offset in time from the parent plant.

Did your plant have multiple trunks? If so, it was actually multiple plants. If not, you possibly had a plant with a novel mutation that could have been very lucrative.

Totally, I can explain that. There can be a couple of things going on. You can start with environment, where you are. I had a couple banana plants for about 15 years in Ireland. Red banana and dwarf banana, they're grown for their flowers but they did produce fruit and then continue to live. They were indoors, so they never overwintered. They also were not in a subtropic climate, so when they did fruit it was only one stem and not the whole plant. When I'm talking about cultivation of Bananas, it's the Cavendish banana. Which is your chiquita banana, del monte cultivar. That are grown and maintained in the proper climate, with yearly crop cycles outdoors and they're all sexually sterile triploids. Bananas you get from a nursery are not the same and so different varieties in sub-optimal climates will behave differently. Fruit production is driven by ethylene, it's the phyto-hormone that produces female flowers seeds. Like Cannabis, Bananas are a heavy nitrogen feeder.

To get optimal growth you want to keep your Ph floating between 5.5 and 6.5 because that is the range where you get the most nitrogen absorbed whilst still getting required levels of Phosphorus and Potassium. Demand for Phosphorus and Potassium goes up during flowering because you need them for ethylene production. So, if you have insufficient levels of Phosphorus and Potassium, you'll get in a situation where it could be pollinated and even start to fruit, but be unable to complete the process. So it doesn't all die back. People think of flowering/fruiting as set parts of a plant's lifecycle, but biology (especially when you're caring for a plant in a man made environment) is messier than that. If you grow any photoperiod plant indoors, under LED light, you can demonstrate this really easy. It's possible to reverse it and go back into vegetative growth. Used to be a popular method with amateur cannabis farmers.

They'd swap a plant into flowering by changing the light cycle, which causes the plant to start producing higher levels of ethylene and stretch. It's like a big shot of growth hormone, plants can double in size in a matter of two weeks sometimes. Then they'd swap it back to an 18/6 light schedule and you get really weird gnarled growth at first and then it will start to produce normal fan leaves again. Then after a few weeks, they'd flip it to flower and it would get that same big boost to vegetative growth again. Which was handy when you're growing one plant to yourself and your mates indoors. Totally impractical for commercial cultivation. If your banana wasn't producing flowers those years it was stalled, it wasn't gonna produce fruit. Equally conditions (lets say low P-K levels) only allow for part of the plant to produce flowers. Only the that part of the plant will have the potential to produce fruit.

I don't know, specifically, the conditions that caused your plant to behave like that. But, it's almost 100% going to be some factor of environment. Light, humidity, nutrient content of the medium. Say your humidity is really low, your banana leaf is still going to grow, but the rate at which gas exchange will occur will be totally different. So, they won't absorb the necessary Co2, which they need for for cellular respiration through creating ATP. Like most plants, banana and Cannabis are type C3 plants. So they only bind Co2 when the light is on them. So, if you have reduced levels of light, not through yearly seasonal changes, but like shade. They will grow much much slower, because PAR is logarithmic, so even a little bit of crowding out, or shading means massively reduced levels of light.

If I was a betting man, I'd say just insufficient nutrients/light to complete the fruiting cycle. Also, when I say they die after fruiting, they die back to their root, essentially. Which throughout the growth cycle is proliferating new rhizomes. That will grow out of the same area that the primary plant was. They don't "die" and that's it it's nothing. They reproduce through fruit and through the kind of natural cloning of the proliferation of rhizomes. Not specifically the Cavendish banana because it's been engineered to produce no seeds. Which is a good place to leave this off with a very fun fact. The Cavendish Banana that's cultivated for sale to international markets, along with seedless watermelon, seedless grapes etc. are as I mentioned before, what we call Triploids and I'll end it here.

Ploidy in plants is comparable to chromosomes in people. Normally the banana would be a Diploid. In Olericulture specifically, we normally grow triploids, because they are sexually sterile. Crocus extract (also a gout medication in humans) is a tubule inhibitor. Normally, when meiosis occurs and the cell divides to form two gametes you get one cell with half the DNA and the other with the other half. After exposure to Crocus extract, you get 1 gamete that has 100% of the necessary DNA and an empty cell that can't do anything. The offspring of that plant after fertilisation, will be a quadriploid. Just means the DNA of 2 plants contained in one. You cross that with an unaltered diploid plant and the resulting offspring will be a triploid. Because triploids are incapable of producing offspring. Even when they meet pollen, because having 1 and 1/2 times the amount of DNA in the plant means that there's always an unpaired strand of DNA, so the plant never gets the signal to start incubating seeds. The bananas produced by triploids are way bigger and highly prolific as well, just by the nature of their genetics.

Hope that answers your question, sorry about all the extraneous stuff, got me thinking about University for the first time in a decade.

I was agreeing with you that it's silly to correct someone calling it a tree outside of specific contexts, just like arguing a tomato isn't a vegetable.

For what it's worth, I have had to learn the growth habits of plants in ecology classes for a degree that I am currently earning. I have plant identification books that use those terms, because they do have a technical use.

You seem to be making two points here:

1. That people colloquially call it a tree, so don't "correct" it. We know what they are talking about.

That seems fair enough.

But then you seem to say that:

2. There is no definition of what a tree or herb is so you can't separate the two. The term is used to describe non woody growth that dies back (among other things). How can you say the word herbaceous is not a testable definition?

I don't think it is pedantic at all. I have a banana patch, and I certainly consider them bushes instead of trees. I think people are interested in finding out the trivia that a banana tree is not a tree, but an herb.

Confidently Incorrect. You, sir/madam are the pedant. Who does not understand the field in which I work. Which is why you mistakenly think clade, has anything to do with classification of herbivorous plant, or woody tree.