Past 3 days, I've been digging the 3' diam. stump, about a foot deep, but m any fibrous/spaghetti-like/spindly root system. I've heard these types of plants have calcium crystals inside and, if so, the chain saw would dull f ast, which it did, real fast. The "wood" is spongy and full of water.
Most noted, there are no earth worms or other typical bugs in the soil, adj acent to the rootball. Not even any June bug larvae, in the soil. The tr ee/sap stunk, badly, and it didn't take long for house flies to gather on t he cut surfaces, apparently eating/drinking something.
There must be some chemical in these plants, such that worms and bugs aren' t in the nearby soil. I found that strange.
There were amaryllis lilies planted around the yucca. The soil conditions had no effect on the flowers' growth. They grew well.