Hearts of Palm are actually my favorite food. As far as killing a whole tree goes, it really depends what kind of heart of palm you are eating. If you live in the US, then you are probably eating heart of palm from a peach palm which has several stalks as opposed to the single stalk in the coconut palm. The peach palms are cultivated in Costa Rica, so check the can you are eating them from and make sure they are from Costa Rica, and therefore more ecologically sound.

FYI
A salad containing hearts of palm is also known as a "millionaires salad"

I also love hearts of palm--get them in organic cans at Trader Joe's. They are from Peru. I hope that by eating these little delicious yummies I am not doing environmental damage to the world.

The 'heart of palm' is the apical meristem (i.e. the growing tip) of a palm. Harvesting it does kill the shoot it is taken from and most palms have only one shoot. On the other habd, the rest of the plam recycles into the earth as nutrients for the next generation -- that is, plants are made from air, water, sunlight, and small quantities of soil minerals (nutrients). The only thing possibly not in plentifu supply is the nutrients: the quetions are: (1) by removing the hearts, are you removing significant nutrients which are not replaced? (probably not); (2) are the trees wild or cultivated, and if wild, are they being depleted? As to the second quetion, I do not know the answer though an earlier answer says multiple shoot plams are cultivated in Costa Rica.

http://en.wikipedia.org/wiki/Heart-of-palm - seems to clarify this discussion

One thing that I know: the BEST one is from Brazil. If you try it…you don’t want to eat from someplace else. They are firmer,tastier,and bigger. yummyyyyyy!!!