>A pecan tree purchased from a nursery will reach its full height of four to six feet in 8 to 10 years if planted in the right spot.

That has to be a dwarf variety. I have seen pecan trees that are more than 80' tall or about half as tall as an Olympic swimming pool is long, with a crown diameter of over 110' or about 2/3 as long as an Olympic swimming pool. The trunk at chest height was more than 3 grown men wide, or about 1/10 the width of an Olympic swimming pool.

These trees get large and if they were solid objects their volume could store nearly as much water as an Olympic sized swimming pool. That is just the part above ground that we can see. Remarkable trees.

Pecan is furniture grade wood like black walnut and commands a premium. It is also prizes for smoking meats as it lends a nutty flavor to the brisket. It's my favorite.

When a pecan nut sprouts it sends all of its initial energy burst into growing a tap root, looking for the best source of dependable water, before you see any top growth at all above ground. Typically if your pecan tree seedling is 1' tall the tap root will already be more than 3' long. This is why nursery pecans are sold in planters that are about 3X taller than they are wide, so that the root is less likely to be coiling inside the pot. You don't want to strangle the tree by letting it become pot-bound.

This is why pecans need relatively deep soil with near surface water. If they have a dependable water supply they can stab that root through any crack and you will eventually have a huge, very productive nut tree.

Pecans are awesome trees. Mine have fed a murder of crows for several crow generations. They show up on the pecans every year about 2 weeks before the nuts are ripe enough to harvest and they strip my trees from the bottom up so that over the years, I have been able to harvest less than 5 buckets of pecans from 5 trees. Very efficient. I think they start at the bottom specifically to deprive me of the ones that are easiest for me to harvest. I surrendered the pecans to the crows a long time ago since they had a much more efficient system of exploitation than any I could conjure. I know the man who planted the trees had fought the same battles with them as I found the rubber snakes and the sad remains of a plastic owl in the trees while climbing them to assess their health right after we bought the place.

I'm on pretty good terms with the crows now. One has learned to ask for peanuts and I'm accommodating enough to provide them, almost on demand.