Ths 9 foot saguaro looked normal all through last fall. I watered it several times in the summer and fall because we had no rain at all. The ribs stayed skinny, but the color was OK. In february, the saguaro looked a bit paler green, and from March on it has had a yellow area spreading on the north side to nearly half way down. The ribs in this area area almost tan.No rot, soft spots or bugs. People tell me to water it, and I have since it warmed up - but the yellow keeps spreading.