Up the page I asked why one AC was big and another AC small in a side by side comparison, and also why one Bur Oak was large and another small in a side by side comparison? Both sets of trees were not tubed or fertilized. They were watered enough to ensure survival, yet one bur oak was much larger than the other and one AC is much larger than the other.
Actually this was an experiment I started about three years ago.
This is the big AC.
This is the small AC.
These are the two AC, with the smaller in the foreground.
The extreme difference in growth is that the larger trees have 5'x5' Lumite weed mats, and that's the only difference. Lumite weed mats are the only way to go in dry climates, and even in moist climates, because Lumite keeps away competing vegetation, allowing for Sun, moisture and nutrients to be available throughout the entire growing season, plus Lumite serves as a moisture barrier to retain moisture evaporating up through the soil.