[Avodah] What's the berakha on hearts of palm?

[Zev Sero]

Micha Berger wrote:

> If the tree's major consumable is something other than a fruit, it
> could still be a ha'eitz. (However, they still are exempt from orlah -
> YD 294:2.)

How can this be so?  How can the tree itself be called its own fruit?
Surely it's the fruit of the ground that produced it.  Where is the 
source for this?

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Zev Sero                      The trouble with socialism is that you
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