Answer:
From the stored sugar inside the stem and branches.
Step-by-step explanation:
The maple trees get their energy at the beginning of spring from the sugar that is stored in the stem and branches because there is no leaves present at that time. Leaves produces glucose during photosynthesis process but in the winter season, the maple tree losses all its leaves so when the spring season comes and the leaves begin to sprout, the maple trees need energy so it used the sugar that is stored in its branches and stem for the generation of energy.