A small tree on the roadside bears many green fruits. It's hard. What kind of plant is this? Is it poisonous?

This is Lagerstroemia speciosa, 7-25m high. The bark is gray and smooth. Positive plants. Need strong light. It is heat-resistant, cold-resistant, drought-resistant, alkali-resistant, wind-resistant, semi-shaded, shear-resistant and pollution-resistant, and it is difficult to transplant big trees. It likes high temperature and humid climate, can adapt to full sunshine or half sunshine cultivation, is not strict in soil selection, and is wind-resistant, cold-resistant, drought-resistant and barren-resistant. There is no poison, and the roots and leaves are still Chinese medicine.