In a pot experiment, the clonal ramets of Cynodon dactylon, the stolon herbaceous plant, were treated with heterogeneous lighting. Shade stress was carried out on the distal ramets (younger ramets) to three different degrees, and the stolons between the proximal ramets and distal ramets of each pair were treated in an intact or severed manner. The results show that in moderate shade stress, the stolons severed significantly decreased the biomass and net photosynthetic rate (Pn) of distal ramets, and that in serious shade stress, the stolons severed significantly reduced the number of ramets, the number of leaves, biomass, net photosynthetic rate (Pn), the maximal quantm yield of the photosystemⅡ(Fv/Fm) and the effective quantum yield of PSⅡ(ФPSⅡ) of the distal ramets, and that clonal integration alleviated the negative effects of shade stress on the growth of distal ramets. In moderate shade stress, the stolons being intact significantly increased the net photosynthetic rate (Pn) of proximal ramets. In the serious shade stress, the stolons being intact effectively improved the maximal quantm yield of the photosystemⅡ(Fv/Fm) and the effective quantum yield of PSⅡ(ФPSⅡ) of the proximal ramets. Thus, clonal integration drove the photosynthetic rate of the unstressed proximal ramets to compensatory increase. In contrast to the treatment of the stolons severed, clonal integration would significantly reduce the biomass of the unstressed ramets, but result in no significant change of the whole clonal fragments when the distal ramets were treated with serious shade stress. Therefore, when the distal ramets suffer from serious shade stress, Cynodon dactylon, the stolon herbaceous plant, may take a risk-spreading strategy to reduce the death of genets, which is of vital importance to maintain the fitness of the genets of clonal plants in heterogeneous environments.