Methods and compositions for increasing the starch content in green tissues of a plant are provided. The method comprises down-regulating me activity of starch degradation enzymes in a plant. The resulting transgenic plants of the invention have increased starch content in green tissues and exhibit a starch excess phenotype. In one embodiment the method involves manipulating a monocot plant to down-regulate the activity of a starch degradation enzyme. The plants are useful for improving the yield of free sugars from plant biomass and increase dried green tissue storage stability.
