The Life Cycle of an Acorn Seedling Into a Tree

"Mighty oaks from little acorns grow," or so the old proverb says. When you hold a tiny acorn in your hand, it's sometimes hard to imagine how such a small seed can grow into a large, sturdy tree like the oak tree. The transformation of the acorn into sapling and then mature tree is a risky process and only a tiny proportion of acorns make the transformation from seedling to mature oak tree.

The first stage of the acorn seedling's life is fruiting. The acorn grows on the oak tree through the spring and summer shortly after the tree has flowered in the spring. Toward the end of the summer or in early fall, fully grown acorns from white oak trees fall to the ground. Acorns from red oak trees fall during late fall or winter.

Acorns are heavier than many tree seeds and usually fall to the ground close to the parent tree. Acorns rarely sprout or germinate when close to the parent tree due to lack of light through the tree's canopy. This function is performed by squirrels and other rodents that scatter, hoard and eat the acorn seedlings. Those acorns left uneaten have the chance to sprout and grow into an oak tree.

Acorns need the right soil conditions to germinate and sprout. They require moist and nutrient-rich soil in a location that gets plenty of sunlight and rainfall. Given these conditions, the acorn will start to germinate and grow a taproot that pushes deep into the surrounding soil. As the taproot grows down, the acorn sends a shoot upward. This is the first stage in its transformation to mighty oak tree.

The seedling tree faces many dangers, from hungry wildlife such as the deer to forest fires and human construction activity. If left unmolested, the seedling will gradually grow and develop into a sapling tree after four to five years. The sapling then grows into a small tree that flowers and produces its own acorns. Many oak trees can live for hundreds of years, fruiting new acorns every spring and summer.