Can anyone please clarify how long the great plains took to create the top soil that was gone before the dust bowl? How many centuries to make a a quarter inch? Any personal stories or information would be greatly appreciated. Thanks

Don't know if anyone really would know that information. Id say a lot of the parent material came. From the last glaciation.

In optimum conditions, soil rate is about 1mm/year so 4 inches in 100 years. Conditions largely depends on what's available to turn into soil, erosion adding to or taking away, organic material, etc.

MNMAN was likely alive during that era.

Does dirt really disappear or does it just get moved around? Back when I paid more attention it was unbelievable the amount of tons that go down the Mississippi. Concrete and asphalt seem to be more permanent but its hard to grow anything on it.

It moves. Generally goes from the high places to lowest.

I can show you washes on my homeplace that you can drop whole houses into. What was there is now probably somewhere in Mobile Bay or the Gulf.

Here's one in Georgia.

https://en.m.wikipedia.org/wiki/Providence_Canyon_State_Park

And killing beavers.
And killing beavers.

Have a friend who is a retired dentist in Harpers Ferry WV. He had husband and wife patients from the plains states. The wife grew up in a sod house with newspapers on the inside walls.

I might be old, but not older than dirt just yet. Dirt was invented at least 5 years before my birth.

At one time it was believed to take about 500 years to produce 1 inch of topsoil especially in farming conditions, now ISU is beginning new research as with advancements with notill and other cropping practices they are beginning to believe that topsoil can be produced faster. Here’s a link to Nebraska government dust bowl.

https://history.nebraska.gov/publications_section/dust-and-snow/

Lot of the regenerative farmers are finding. I know one farmer that no tills and he said his earthworm count per acre is insane since going to ot.