Trees are connected to other trees around them by a network of fungi underground called a mycorrhizal fungal network. Chemicals are sent from tree to tree through the fungus, in a kind of communication that can take hours to detect and centuries for humans to even notice. If this were only a transfer of chemicals, we wouldn’t call it communication, but new research led by Dr. Suzanne Simard of the University of British Columbia shows that trees send different chemical messages to each other depending on conditions. For example, when researchers shaded one tree, a nearby tree of a different species began sharing nutrients with it. But trees prefer to share with their close kin.
"If you're a mother and you have children, you recognise your children and you treat them in certain ways. We're finding that trees will do the same thing. They'll adjust their competitive behaviour to make room for their own kin and they send those signals through mycorrhizal networks," says Simard.
"We found that the biggest oldest trees had more connections to other trees than smaller trees. It stands to reason because they have more root systems," she says.
"So when a seedling establishes on the forest floor, if it's near one of these mother trees it just links into that network and accesses that huge resource network."