How Do Plants Communicate?

People communicate with each other through spoken and written words and actions. We also know that animals communicate by using sounds and movements. However, we may not be aware that plants talk to each other. They don’t do it by speech, writing, sounds, or movements. Since they are stationary and silent, how do plants communicate?

Plants are continuously engaging with other plants in their environment, mostly underground. For example, the roots of most plants host fungi, and working together, the plant roots and the fungi create underground structures called mycorrhizae. These mycorrhizae resemble a web system surrounding the plant’s roots, helping the plant absorb nutrients such as nitrogen and phosphorus in a symbiotic relationship. As the mycorrhizae help the roots absorb essential nutrients and water, the plant uses photosynthesis to produce sugars which it shares with the fungi.

But how do plants communicate? The mycorrhizae can connect multiple plants into a network through which they can share energy and information. This web creates a fine-tuned community-wide sharing system. Through this communication channel, plants can pass defensive chemicals to protect against insects. When pests such as aphids attack a plant, it can send a message to its neighbors so they can preemptively activate defense responses. In this way, mycorrhizae enable a system of cooperation between plants.

However, when resources such as light or nutrients are scarce, a plant can limit its mycorrhizae connections and avoid making new ones. Then when resources are good, they can restore their sharing network and even make new connections. When the plants connected in the mycorrhizae network are closely related, they share more than if their neighbors are not close relatives. Trees use these fungal networks to communicate and share but also sometimes to sabotage their rivals. Plants determine when to share and when to maintain their independence.

As we investigate the question, “How do plants communicate?” we realize that they behave as humans often do, putting their own interests first. Yet, sharing and working together is part of God’s design for life, and humans should always follow the example set by Jesus in His life and teaching. (See Matthew 5:38-48 and 25:31-46.)

— Roland Earnst © 2022

Reference: The Conversation