Other than having spikes, living in deserts, and taking 10 years to grow their 1st inch, then not reaching 6ft for 75 years, they’re pretty much like trees right? uh…no. Their root system is different. They send one single root deep into the ground called a TAPROOT. This extends only about 5ft, because the soil is very firm as it’s mostly clay. But Saguaro cactus, the largest cacti and endemic to North America, does it differently. Remember they can grow up to 75 feet tall that’s 7 stories but send they send their roots to only a few inches below the surface and spread them out, more like trees in this case. This allows them to collect a lot of rain water and save it for a rainy day? Not sure about that one. Take a look.