Fungi help the trees absorb nutrients and resist insects. Decayed trunks build soil or hold water like a sponge. The tall trees trap and hold moisture. Branches and needles catch dust and dirt, thus cleansing the air. Plant photosynthesis removes carbon dioxide gas from the atmosphere.
Roots bind soil against erosion.
They also bring a better price. They have more 10 to 20 growth rings per inch compared to three to six rings in a smaller tree. It is a fact that Sequoia trees have economic value. Sequoia wood is so strong and naturally resistant to moisture and insects. Yet, those qualities can be artifificially applied to inferiror timber when treated with preservatives.