If the spike is starting to yellow, it is safe to remove it. As Karen said, some leave it on until it is brown, as its nutrients and stored energy are being absorbed by the plant. Either one is OK.
thank you very much. i was so afriad it was dying, LOL.
i didnt realise that they grew new spikes when they started blloming, i figured that they kept the spikes they had and just added to them as it go older...
The first time I saw a spike turn yellow, I thought I had killed the whole plant. Alas, it is just the circle of life! Maybe you will get an ever BIGGER spike next time. (crosses fingers)