A large part of western Manatee County is devoted to the growing ofwinter vegetables and citrus fruits. As in most of peninsular Florida,rainfall in the county during the growing season is not sufficient for cropproduction and large quantites of artesian water are used for irrigation.The large withdrawals of artesian water for irrigation result in a considerabledecline of the artesian head in the western part of the county. This seasonaldecline of the artesian head has become larger as the withdrawal of artesianwater has increased. The lowering of the fresh-water head in some coastal areas in the Statehas resulted in an infiltration of sea water into the water-bearing formations.The presence of salty water in the artesian aquifer in parts of the coastal areaof Manatee County indicates that sea water may also have entered the waterbearingformations in this area as a result of the decline of artesian pressureduring the growing season. The purpose of the investigation is to make a detailed study of the geologyand ground-water resources of the county, primarily to determine whethersalt-water encroachment has occurred or is likely to occur in the coastal area. (PDF contains 38 pages.) | Prepared by the GEOLOGICAL SURVEY UNITED STATES DEPARTMENT OF THE INTERIOR Sin cooperation with the FLORIDA GEOLOGICAL SURVEY the BOARD OF COUNTY COMMISSIONERS OF MANATEE COUNTY and the MANATEE RIVER SOIL CONSERVATION DISTRICT

Topworking — or topgrafting — to change varieties found unsatisfactory for growing in the avocado orchard at Riverside is used instead of planting a new young tree because a topworked tree comes into production several years sooner and the quality and performance of a new variety can therefore be evaluated earlier. Topworked trees have ranged in age from six to 10 years.

Five one-tenth acre plots were established on Lee Forest to investigate forest site and type and soil relationships. One plot was in each of the following types and sites: western hemlock-Douglas fir, site class III; Douglas fir, site class II; Douglas fir, site class III; western red cedar, site class III; red alder, site class I. Soils were sampled on these plots and the following data taken: effective depth, bulk density, texture, moisture equivalent, reaction, total nitrogen, and cation exchange capacity. In addition, weight and nitrogen content of the forest floor were determined and soil moisture followed throughout the 1953 growing season. Depth to a hardpan layer was an important criterion for productivity rating. High bulk densities impeded root growth and determined effective soil depth. The critical density differed for the different tree species. Total soil nitrogen and total cation exchange capacity were much greater in the more productive forest soils. The western red cedar and the red alder plots had shallow soils with excess soil moisture during a considerable portion of the year. Low soil moisture did not appear to be a factor in tree growth on any of the plots in the 1953 growing season although the soil on the red alder plot did become quite dry in late August and early September. The dominating influence in determining forest type seemed to be poor soil drainage.