on the ajusco volcano, mexico city, mexico, pinus hartwegii seedlings were planted in five treatments: ne side of lupinus montanus plants, ne side of penstemon gentianoides plants, between festuca tolucensis grasses, in small openings where grasses were cleared away, and in small natural gaps among the grasses. mortality, diameter, height, biomass and foliar nutrient concentration (n, p, k) were evaluated six (dry season) and 12 months (rainy season) after tree-planting. photosintetically active radiation (par) was measured with hemispheric photographs and the program hemiview. mortality was analyzed using logistic regression, while morphological and physiological variables were analyzed with multivariate variance analysis. also was employed analysis of variance. there were no differences in mortality (average of 15 %) among treatments. the anova showed higher trees in the lupinus, penstemon and cleared treatments, in comparison to grass and small natural gaps treatments (p<0.10). the manova exhibited higher tree leaf concentrations of n and k in the seedlings associated to lupinus one year after planting date in the rainy season, in comparison to the grass treatment, and higher n concentrations than the clearing treatment (p<0.10). the par was lower when the seedlings were associated to plants, but did not limit the growth of seedlings. is recommended the use of lupinus as nurse plant associated to pinus hartwegii.