What can be said about food reserves in plants just after leaf expansion?

After leaf expansion, food reserves in plants are typically at their lowest. This is because during the process of leaf expansion, the plant is heavily investing in growth and development, utilizing stored nutrients and carbohydrates to support the formation and expansion of new leaves. As the leaves grow, they require significant energy and resources to develop fully, leading to a depletion of the food reserves that were previously stored in the plant.

Once the leaves are fully expanded and begin photosynthesis in earnest, the plant can then start replenishing its food reserves as it produces new energy through the conversion of sunlight into chemical energy. Hence, immediately after leaf expansion marks a critical point where reserves are consumed for growth, resulting in a lower level of stored energy in the plant.