Is this true?

[Leafmite]

Discussion is a good way of learning.

I am always doubtful about declarations of new discoveries when there are not enough trials (that follow the scientific method and eliminate other factors) to prove beyond doubt a 'conclusion. 'Science news' that is not peer reviewed or proved with other trials should be taken with a grain of salt.

It has been discovered that plants use chemicals to communicate, to deter pests, attract pollinators, and even to close parts of themselves around insects (CP's). A few have been observed to kill competitors with chemicals (nothing grows around them...consistently).

When it is beneficial to the plant to eliminate competition, there are more effective ways to do this...growing faster and putting out a thick canopy, quickly sending out plenty of offsets, seeds, root growth, having roots that drain and store all the possible water/nutrients, etc. Plants that are alone are more likely to be eaten by something (especially tender, young plants) so it is to their benefit to survival to use one of these other methods so that they are big enough to survive an attack when they are alone instead of wasting energy on chemical warfare.

[Ray]

Originally Posted by Leafmite

It has been discovered that plants use chemicals to communicate, to deter pests, attract pollinators, and even to close parts of themselves around insects (CP's). A few have been observed to kill competitors with chemicals (nothing grows around them...consistently).

When it is beneficial to the plant to eliminate competition, there are more effective ways to do this...growing faster and putting out a thick canopy, quickly sending out plenty of offsets, seeds, root growth, having roots that drain and store all the possible water/nutrients, etc. Plants that are alone are more likely to be eaten by something (especially tender, young plants) so it is to their benefit to survival to use one of these other methods so that they are big enough to survive an attack when they are alone instead of wasting energy on chemical warfare.

I cannot see how the production of eentsy, weentsy, teeny, tiny chemicals is more wasteful than the production of chemicals for growth. More mass takes a lot more resources.

I would think that a tender, young plant would be more likely to use “chemical warfare” precisely because it is relatively unprotected by size.

[Leafmite]

I think the reason we do not see much of plants using chemicals to eliminate other plants is that plants do not find it as beneficial. It is more effective to grow and produce more mass (more leaves mean more photosynthesis, more plants mean a better chance of survival for the species when adversity strikes).

A good example is an organic vegetable garden or flower bed...and weeding. Or the attempt to remove difficult to eradicate invasive species. These are the wildly successful plants. They are successful not by killing their competition with chemicals but by explosive growth. It would be so much easier to eradicate these plants if they chose to kill their competition with chemicals. It is not very difficult to clear a forest or yard of young Black Walnut trees.

I think this is just why we do not see it as often.