A Norfolk pine
The stem or trunk, not sure what it is called but it is so so long, I want to replant the plant but I want to know how to shorten up the trunk. Can I cut it short? Or will it die?
Certified GKH Gardening Expert
Although it may not die, it will change the way it grows. It will never retain the shape of a typical pine after you do this. This can get quite tall. If it is kept in container, then you can expect a height of about 6 feet. If it is planted in ground, then you can expect a height of up to 200 Feet. This pine can get massive. If you do cut it, then the shortening will only be temporary. After awhile, the multiple new tops will reach the same height. Alternatively, if it seems to be stretching to reach light, then you will need to put it in an area that gets more sunlight if it isn't already.
The decision is up to you, ultimately. It will not harm the tree, but will affect how it looks in the future.
Here is a link to a collection of articles on their care: https://www.gardeningknowhow.com/houseplants/norfolk-pine/