| Number | Name | Date | Kind |
|---|---|---|---|
| 1010819 | Thompson | Dec 1911 | |
| 3767124 | Spencer | Oct 1973 | |
| 3863845 | Bumpstead | Feb 1975 | |
| 4058257 | Spencer | Nov 1977 | |
| 4193545 | Havens | Mar 1980 | |
| 4509692 | Moss | Apr 1985 | |
| 4589595 | Havens | May 1986 | |
| 4613080 | Benson et al. | Sep 1986 | |
| 4660769 | Rosenberg | Apr 1987 | |
| 4726527 | Mendenhall | Feb 1988 | |
| 4765541 | Mangels et al. | Aug 1988 |
| Entry |
|---|
| Olson Irrigation Systems Brochure, Dec. 1, 1989. |