@article{Santos:256965,
      recid = {256965},
      author = {Santos, B. M. and Morales-Payan, J. P. and Dusky, J. A.  and Stall, W. M.},
      title = {EFFECTS OF PHOSPHORUS FERTILITY REGIMENS AND COMMON  LAMBSQUARTERS (Chenopodium album) INITIAL REMOVAL TIMES ON  LETTUCE (Lactuca sativa)},
      address = {1997-07-06},
      number = {1887-2017-781},
      pages = {5},
      year = {1997},
      abstract = {Field trials were carried out in organic soils naturally  deficient in phosphorus (P) fertility to determine the  effects of different fertility regimens of this nutrient  and common lambsquarters initial removal times on lettuce  marketable yields. Phosphorus was either banded (125 Kg  P/ha) or broadcast (250 Kg P/ha) prior to lettuce planting.  A single lambsquarters population density of 4 plants per  5.4 m2 was allowed to interfere with "South Bay" lettuce  within each Ρ regime. Lambsquarters were removed at 2, 4, 6  or 8 weeks after lettuce emergence, along with the  weed-free control. When lettuce was grown under weed-free  conditions, banded Ρ increased lettuce marketable yields by  27% compared to Ρ broadcast. With banded P, no significant  differences were observed between the 2 week removal and  the weed-free control. On the other hand, differences were  accounted between the weed-free control and the 2 week  removal (aproximately 24% reduction). No differences on  lettuce marketable yields occurred after 4 and 6 weeks for  broadcast and banded P, respectively. Maximum yield  reductions of about 47 and 51 % for banded and broadcast Ρ  were measured. These findings suggest that banding Ρ in  lettuce stands increase the time of lambsquarters  interference necessary to reduce lettuce yields.},
      url = {http://ageconsearch.umn.edu/record/256965},
      doi = {https://doi.org/10.22004/ag.econ.256965},
}