Question

Does insectivorous plants completely digest the insects if no where does the waste product go ?

Answer 1

In venus fly which is a insectivorous plant, traps after the plant gets what it wants the trap open and what’s left is blown away, or the trap dies. In pit fall carnivorous plants the waste remains until it is washed out (rarely) or until it decomposes (more common), or until the leaf dies (most common, IMHO).

Plants do not actually eat; they take in CO2 and make sugar (food) and expel O2 as a byproduct (waste). They also use O2 to metabolize sugar, and put out some CO2, but they put out far more O2. Carnivorous plants are not exactly eating the animal as we do, just digesting the stuff they need and ridding themselves of the chiton and other indigestible stuff when the leaf dies. Their needs are Nitrogen, Potassium, Phosphorus, some Iron, and a few other things. The proteins in the animals are only usable as Nitrogen. No real need to expel waste.