Can plants learn? Do they communicate with each other? Can they change their environment to survive? The intelligence of plants is a trendy new field of study among botanists and scientists.
In 12/2015 National Geographic Magazine ran an article about the Sensitive Plant (Mimosa pudica.) The Sensitive Plant is amazing because when touched, it folds up its leaves and lowers its branches to protect itself from harm. I try to purchase one every year because it is such an unusual novelty. In the article the scientist sat up an experiment where a mechanism was developed in which the plant was repeatedly dropped six inches and it would fold up its leaves and branches to protect itself. They continued to drop the plant, and after a while the plant realized it would not be harmed, and it stopped folding up. They sat the plant aside for 28 days and dropped it again. The plant appeared to remember falling would not harm it and it did not fold up!
The Dodder Vine is the vampire of the plant world. It is a parasitic vine that blooms and sets seeds. It’s seeds germinate and soon the roots die and the vine finds a host to attach to and suck out nutrients. The Dodder Vine especially enjoys attacking tomato plants. Slow motion photography shows a baby Dodder Vine reaching skyward hunting for its prey. When it senses a nearby tomato plant it attacks! A few years ago I bought a hanging basket infected with a Dodder Vine. The vine traveled several feet and wrapped itself around one of my tomato plants. It traveled past and over many other flowers and plants before finding the tomatoes in a raised bed. I tossed the hanging baskets in the trash, and they were taken by someone. I hope they didn’t have a garden full of tomatoes!
Many plants, including Walnut trees release a toxin into the soil that inhibits the germination of other plant seeds. By poisoning the soil to any competitors, they are free to grow large populations of their offspring and not have to worry about other plants invading their territory.
In the south western U.S. Wild Tobacco (Nicotinia attenuata ) blooms during the night to attract nocturnal moths to spread pollen from plant to plant. The moths sometimes lay eggs and produce very hungry caterpillars that make a feast out of the plants. To protect itself, the tobacco releases a chemical that attracts insects that eats the caterpillar eggs. If the eggs are to plentiful or the helpful insects are not available, the tobacco secretes a sugary substance. The caterpillars love to eat the nectar, turning them into juicy sweet smelling bug candy and are very tasty to predators like lizards! But if all of these fails, the tobacco has a plan B. They simply change their flowering time to day, attracting hummingbirds that pollinates them!
Plants use sunshine through the process of photosynthesis to provide itself with nutrients. For years botanists have wondered how tree seedlings survive under the dark shaded canopy of the mother tree. Radioactive isotopes were injected into the mother tree. Later when the seedlings were checked they contained the same isotopes. The mother tree feeds the tiny seedlings until they are large enough to produce their own food!
Trees seem to be able to communicate changes in climate, harmful viruses, insect attacks or soil changes to other trees. Scientific research has shown trees transmit and communicate through their root systems. But how is the vital information communicated when tree roots are not close enough to other trees? It has been theorized they use fungus within the soil to act as a go between from tree to tree and perhaps to an entire forest!
In the 2008 science fiction film, ‘The Happening by Director M. Night Shyamalan, large sections of the US population is dying from an unknown airborne toxin. At first, it was felt it might be a terrorist attack, but scientist soon realize trees are producing and releasing the toxin. In a sense the trees were getting revenge for man’s intrusion and harming the plant kingdom.
When we sit under the shade of a large maple or enjoy the sweet scent of a rose, perhaps there is much more going on in the life of plants than we realize!
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