Calcium, K, Mg, Na, P, Cu, Fe, Mn and Zn contents were determined,
seasonally, during two consecutive years in leaves of native browse
plants such as Castela texana T. & G. Rose (Rutaceae), Celtis pallida
Torr. (Ulmaceae), Forestiera angustifolia Torr. (Oleaceae), Lantana
macropoda Torr. (Verbenaceae) and Zanthoxylum fagara (L.) Sarg
(Rutaceae) growing in rangelands at northeastern Mexico. All minerals,
in all species, were significantly different among years, sites and
seasons and interactions were also significant. In general, plants in
Linares county site, that had the highest rainfall had higher mineral
content followed by Los Ramones and China counties; Moreover, during
summer all plants had higher mineral content followed by autumn, winter
and spring. Regardless of spatio-temporal differences, all plant species
had suitable levels of Ca, Mg, K, Cu, Fe and Mn to satisfy range
domestic and wild ruminant requirements. Nonetheless, P, Na and Zn
showed marginal inadequacies in some seasons throughout the year.