04904112 is referenced by 22 patents and cites 5 patents.

An inner pipe having a plurality of apertures on a top surface is connected to a pressurized water input source. The inner pipe is located within a slightly larger outer pipe and rests on a bottom inner surface of the outer pipe. The outer pipe is buried just below a plant root line. A series of longitudinal slots on a bottom portion of the outer pipe permits water flowing from the inner pipe to the outer pipe to trickle unimpeded into the surrounding soil.

Title
Underground irrigation system
Application Number
7/385565
Publication Number
4904112
Application Date
July 26, 1989
Publication Date
February 27, 1990
Inventor
Carroll W McDonald
3680 42nd Way S., #D, St. Petersburg, 33711
FL, US
IPC
E02B 13/00
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