Q.Saguaro Is Leaning And Has Developed A Crack
At the beginning of last summer I noticed that a 10′ tall saguaro in my yard had started to lean. I reduced the water to the plant and moved the drip lines further away from the base. When we returned to our home this fall we noticed that it had developed a large crack at the base of the plant. I understand that this could be from over storage of water. Is there anything besides stopping the irrigation all together that I should do about the leaning or the crack?

Certified GKH Gardening Expert
Unfortunately, overwatering needs to be mitigated, immediately, with a fungicide. If action isn't taken, you will start to notice symptoms like these.
Leaning might be corrected by propping it with a board, or tying it up to something sturdy.
Correcting the crack won't happen. What you will have to do, though, is to control the bacteria that will take that spot over.
Here are two articles that will get you started: https://www.gardeningknowhow.com/ornamental/cacti-succulents/saguaro/bacterial-necrosis-of-saguaro.htm
https://www.gardeningknowhow.com/garden-how-to/info/using-fungicides-in-garden.htm