Walnut trees are also called walnuts. Walnut kernel is rich in nutrition and is a good tonic. Walnut, almond, cashew nut and hazelnut are called "four big nuts" in the international market. Walnut trees adapt to the ecological environment of deep and loose soil, fertile and moist soil, light-loving, slightly acidic to slightly alkaline soil with good drainage, developed root system and cool climate. In summer, you need to use pesticides properly, otherwise you will attract insects.