Imagine trees are like people holding hands underground. They use tiny threads made of fungi to connect with each other.
Sharing and Warning
When a tree gets hungry, it can ask its neighbors for sugar from the sun. If a bug starts eating its leaves, the tree sends an alert through the soil. The neighbor trees hear this "hello" and get ready by making their leaves taste yucky to bugs before they even arrive.
Why It Matters
This underground web helps the biggest trees help the tiniest saplings grow in the shade. Without these connections, the forest would be lonelier and much harder for young trees to survive.