The present work was developed in the Found Miraflores in the year 2 006, Sector Ahuashiyacu district of the Band of Shilcayo, county of San Martín and Region San Martín, in a floor with characteristics that next is described: texture, sandy Franco; pH, 5,7; match available 7,0 ppm; changeable potassium, O, 19 meq. /100 g of floor. The objective of this work was to evaluate the application of different dosages of Humus, looking for which of these, it is the good dose for the yield of the lettuce (var.: Great Lake). Different parameters were evaluated like: Height of plants, number of leaves, size of roots, production and longitude of leaves as much the long one as the width. The used design was that of Complete Blocks Randomizados with 5 treatments and 4 repetitions, the dosages were the following ones: TO (Absolute Witness), T1 (HUMUS = 1,25 Kg. /1 m2), T2 (HUMUS = 1,37 Kg. /1 m2), T3...