|                                      |   |  State of       |   |                                     |
|-------------------------------------------|--------|----------------------|--------|------------------------------------------|
| Name of Subsidiaries            |   | Incorporation        |   | Names Under Which They doBusiness        |
| Beaver Lake      Concrete, Inc.           |   | Arkansas             |   | Beaver Lake      Concrete, Inc.          |
|                                      |   |                 |   |                                     |
| Capitol Concrete      Products Co., Inc.  |   | Kansas               |   | Capitol Concrete      Products Co., Inc. |
|                                      |   |                 |   |                                     |
| City Wide      Construction Products Co.  |   | Missouri        |   | City Wide      Construction Products Co. |
|                                      |   |                 |   |                                     |
| Concrete      Enterprises, Inc.           |   | Kansas               |   | Concrete      Enterprises, Inc.          |
|                                      |   |                 |   | Concrete Enterprises      South          |
|                                      |   |                 |   |                                     |
|  Concrete      Materials, Inc.       |   |  Kansas         |   | Concrete Materials,      Inc.            |
|                                      |   |                 |   |                                     |
|  Dodge City      Concrete, Inc.      |   |  Kansas         |   | Dodge City Concrete,      Inc.           |
|                                      |   |                 |   | Concrete      Industries                 |
|                                      |   |                 |   |                                     |
|  Joplin      Concrete Company, Inc.  |   |  Missouri       |   | Joplin Concrete      Company, Inc.       |
|                                      |   |                 |   |                                     |
|  Kansas Sand      and Concrete, Inc. |   |  Kansas         |   | Kansas Sand and      Concrete, Inc.      |
|                                      |   |                 |   |                                     |
|  Monarch Cement      of Iowa, Inc.   |   |  Iowa           |   | Monarch Cement of      Iowa, Inc.        |
|                                      |   |                 |   |                                     |
|  Salina      Concrete Products, Inc. |   |  Kansas         |   | Kansas Building      Products            |
|                                      |   |                 |   | Salina Concrete      Products, Inc.      |
|                                      |   |                 |   |                                     |
|  Springfield      Ready Mix Co.      |   |  Missouri       |   | Springfield Ready      Mix Co.           |
|                                      |   |                 |   |                                     |
|  Tulsa      Dynaspan, Inc.           |   |  Oklahoma  |   | Arrow Concrete      Company              |
|                                      |   |                 |   | Tulsa Dynaspan,      Inc.                |