Without making a sound, plants speak volumes. While we may never consider plants great conversationalists, scientists have learned that these silent stalks can and do communicate with themselves and others.

Though plants lack mouths, voices or the usual accoutrements of traditional speech, plants are able to express themselves and share information in their own unique ways. For starters, different parts of individual plants can interact with each other for the best possible outcome. Roots and shoots of a single plant have been shown to collaborate by talking to each other.

We know that roots extract nutrients from soils and shoots take in carbon dioxide from the air. When they are most effectively working together, they can maximize metabolism and growth. To do this, some roots and shoots speak to each other via the phloem (food conducting tissues) using a special protein. This protein moves from the shoot down to the root when the plant needs more nitrogen. Upon arriving at the root, the protein activates genes that increase extraction of nitrates from the soil, and thus increases plant growth to keep up with the photosynthesis happening above ground.

Understanding and manipulating this interaction can help us increase the efficiency of crops that use fertilizers, and decrease the ecological damage of fertilizer runoff by turning the protein on and off as needed.

Plants will also communicate with other plants, though their actions can either help or harm their neighbors. Information can be shared through the air or soil. Think about the smell of cut grass. While many folks consider this a pleasant smell associated with spring, the scent is a chemical reaction to the damage to the grass fibers, a collective grass scream, if you will. The chemicals emitted are volatile organic compounds (VOC) and when one plant releases them, other plants in the area can react and respond.

For example, when an insect eats a plant, that plant releases those VOCs. If other plants detect these airborne

compounds, they may ramp up their defense mechanisms or produce chemicals that make their leaves and stems less palatable to those insects attacking their neighbor. In some cases, plants have even been shown to release a compound that will attract one type of insect that will predate the plant-attacking insect.

Underground communications also occur, and often with the assistance of another organism. Mycelium is the vegetative part of a fungus (sometimes appearing as white fibers in rotting logs and in the dirt) that infiltrates the soil beneath our feet. Mycelium might be considered the underground worldwide web (or maybe wood-wide web), providing the infrastructure for the transfer of information and materials. Since about 90 per cent of land plants are in a relationship with fungi, their interactions are common and widespread.

In one example of collaboration, Douglas fir and paper birch trees were discovered to transfer carbon between each other via mycelia.  Plants can also exchange nitrogen and phosphorous in this way. Large trees can help smaller trees, and trees in shade can receive nutrients from trees in the sun.

Though Dr. Seuss suggested that we speak for the trees because the trees have no tongues, we can take heart in knowing that the trees, while silent, might be able to speak for themselves — if you believe that their actions speak louder than words.

Suzan Bellincampi is director of the Felix Neck Wildlife Sanctuary in Edgartown, and author of Martha’s Vineyard: A Field Guide to Island Nature.