UBC Theses and Dissertations
Mechanizing lettuce production. McLeod, Colin Dale
Economic analyses, which indicated a need for reducing lettuce production costs, were the basis for feasibility studies of mechanizing some production processes. These processes are the thinning and weeding operations. Thinning can be eliminated by precision seeding while weeding can be reduced or eliminated by using a suitable mulch layer. Mechanization of these processes requires development of a mulch layer applying machine and a precision seeder capable of seeding through the mulch. A model of the precision seeder was designed, fabricated and tested. Test results were below the minimum acceptable performance level of the machine. Weaknesses in the model were obvious and modifications are recommended. These modifications should bring the model to an acceptable performance level. A model of the mulch layer applier was also designed and fabricated. Field testing was not completed, however, expected problems are discussed and alternatives are recommended. The practical feasibility of both these machines cannot be completely evaluated until the models have been thoroughly field tested.