This tool is called a sub soiler.  Its a tooth about 4 inches wide and can go down upto 18 inches  It breaks the soil up so water can drain down....This plot will be used as a garden and these drain lines I put into the dirt will help keep the family garden green and not muddy.

The lines follow the grade down to help in draining. 

A hand pick would not penetrate the sod/dirt when I started.. This was in the middle of summer, the few days of summer we did have this year. 

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