What is the primary reason for irrigating newly planted trees?

Irrigating newly planted trees primarily serves the purpose of maintaining moisture in the soil. This is crucial because new trees require a consistent water supply to establish their root systems in the surrounding soil. When trees are planted, their roots are in the process of adapting to a new environment, and adequate moisture is essential for this adaptation. If the soil is too dry, it can hinder root growth, impede the tree's ability to take up water and nutrients, and ultimately stress the plant.

While ensuring nutrient uptake and improving soil structure are important in the overall health of trees, those factors are secondary to the need for adequate moisture right after planting. Without proper irrigation, the soil can dry out quickly, especially in warmer climates or if the tree is planted during the hotter months, leading to decreased survival rates.