This research deals with the taxonomy, geographical and ecological distribution, and the forms of utilization and available empirical knowledge of Agave spp., subgenus Agave, in San Luis Potosí and Zacatecas. The following taxa were found: wild species: Agave salmiana ssp. crassispina, A. scabra ssp. potosiensis, A. parrasana; semicultivated species: A. americana var. oaxacensis; cultivated species: A. mapisaga var. mapisaga, three forms of A. salmiana var. salmiana. A. salmiana ssp. crassispina is the most widely distributed and abundant. It is found from 1 800 to 2 400 m altitude, on igneous and sedimentary substrates, euthric Litosol, and it is an element of the cactus and desert scrubland. It is used to produce mezcal and for the preparation of the edible flowering stem (quiote) . It is the Agave most used as forage, and it is also utilized as construction material, as fuel, in soil conservation, as ornament and as hedge plant. A. mapisaga var. mapisaga and A . salmiana var. salmiana are cultivated principally to the NNW of the city of San Luis Potosí, at 1 880 m, on a deteriorated cactus scrubland. Aguamiel, pulque and honey are elaborated from the natural or fermented juice extracted from the meristem of the plant. There is considerable amount of empirical knowledge regarding the management of this resource. However due to several problems its current use is reduced.
Power Spectrum Measurements from 30 MHz to 910 MHz in the City of San Luis Potosi, Mexico