The diploma thesis on the working tools of mechanisms for crushing unwanted growths in inaccessible terrains and possibilities to increase their service life in the theoretical part on definition of basic concepts and introduces to the issue. It focuses mainly on the theory of processing and removing unwanted growths. It deals with the cutting mechanism - mulching mechanism and design of materials or improving the properties of materials for the production of mulching knives and abrasive wear. The practical part deals with the material analysis of crushing tool used in operation. The result of the experiment is evaluation the suitability of the material which is currently used. For practice recommendations are stated relevant options of the modification for material or its replacement. In conclusion are results of the work evaluated with an emphasis on extending the life time crushing tools.