04019279 is referenced by 35 patents and cites 9 patents.

A tree planter which prevents the roots of a tree from cracking a nearby sidewalk, including a planting container which is buried in the ground with a young tree therein, the container having sidewalls of slick and impenetrable material such as plastic, and with the sidewalls sloping outwardly, so that the open bottom of the container is larger than the top, to help deflect roots downwardly so that when they begin growing outwardly they grow at a level far below the sidewalk.

Title
Root control planter
Application Number
5/585048
Publication Number
4019279
Application Date
June 9, 1975
Publication Date
April 26, 1977
Inventor
Leonard N Albrecht
8780 Shoreham Drive, Los Angeles, 90069
CA, US
Maurice D Moorman
8124 Holy Cross Place, Los Angeles, 90045
CA, US
Agent
Lindenberg Freilich
IPC
A01G 11/00
A01G 9/02
A01G 17/00
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