According to Marie-Victorin the Northern pitcher plant is
"the most extraordinary plants of our flora"Extraordinary, it surely is because, unlike other carnivorous plants, it does not digest its prey by producing enzymes, but rather by a complex association with small invertebrates: the plant captures its prey in its tubular leaves fill with rainwater, thereby forming phytotelmata.
These phytotelmata (water bodies held by plants serving as substratum for associated fauna) contain a microscopic fauna that, for most species in it, live only in the leaves of the Northern pitcher plant.
These little animals shred and mineralized the prey drowned in the water of the leaves, making them available to the plant.
The plant can thus assimilated large insects: flies, ants, spiders and butterflies.