Geology: Soil Systems

1. Maligaya Silt Loam (BW)

These soil types are found in level to nearly level topography with slope that ranges approximately from zero to eight percent and showing no apparent erosion. Some problems with this type of soil however is that they should be protected from water overflow and as such conservation practices should be considered. These types of soil are predominantly found in the southeastern portions of San Jose City, specifically in the following barangays: Tondod, A. Pascual, San Mauricio, Sinipit Bubon and portions of Barangay Sto. Tomas and Caanawan.

These types are mainly used for cultivation of irrigated and non-irrigated paddy rice. During the dry season, onions are alternatively planted on areas not covered by the Pantabangan Dam Irrigation System. Some areas are left idle for years or left covered with grass used for pasture.

This holds true especially for inipit Bubon area where despite its proximity to the main irrigation canal of the Upper Pampanga River Irrigation System (UPRIIS) majority of its agricultural area is still un-irrigated due to its topography.

2. Maligaya Clay Loam (BW)

These soil types are similar to the Maligaya Silt Type series. The area coverage is different however. Its extent goes beyond the Barangay Sto. Tomas area and portions of Barangay Caanawan and Barangay Sto. Niño 3rd. Agricultural activities in these areas are limited to rain-fed palay production with onions and other vegetables as secondary

3. Annam Clay Loam (M)

Another major soil type found along the northwestern and northeastern portion of San Jose City and extending to the boundaries of Carranglan, Pantabangan and Rizal is the Annam Clay Loam. This type of soil is characterized as very severely to excessively eroded or shallow for cultivation and suited to pasture or forest with carefree management. Slope is described as steep or greater than 18% grade.

Forest management in the city is still in its infancy stage as alienable and disposable lands are yet to be defined in the city’s land area. It is for this reason that the city government is currently studying the possibility of entering into a Memorandum of Agreement with the National Mapping and Resource Information Authority to provide the city with accurate thematic maps.

4. Umingan Silt Loam (BS)

Majority of the city’s land area is of this type. It covers the whole poblacion area and its sub-urban sections. Slope is nearly level, making it a good site for urban use. The soil exhibits low fertility, shallowness, draughtiness, slight alkalinity or salinity. With these characteristics, it is advisable to adopt special soil management practices and observe easily applied conservation practices.

The Talavera River bisects this coverage area making the site suitable for onion (red shallots) production. Heavy siltation occurs during rainy season due to excessive erosion of the denuded sections of the city’s forest zone.