Once the agave reach maturity a long stem grows and starts flowering until the flowers releases seeds. This happen only once in agave’s life time, when it turns to red-brown color and dry appearance, they are ready for colection. If the agave is destinated to become mezcal, it has to be castrated; the stem has to be removed before it grows otherwise its not able to produce enough sugar, one of the main reasons agave species are in danger of extinction.