Plants exhibit a wide range of mechanical properties, engineers find

From an engineer's perspective, plants such as palm trees, bamboo, maples and even potatoes are examples of precise engineering on a microscopic scale. Like wooden beams reinforcing a house, cell walls make up the structural supports of all plants. Depending on how the cell walls are arranged, and what they are made of, a plant can be as flimsy as a reed, or as sturdy as an oak.

An MIT researcher has compiled data on the microstructures of a number of different plants, from apples and potatoes to willow and spruce trees, and has found that plants exhibit an enormous range of mechanical properties, depending on the arrangement of a cell wall's four main building blocks: cellulose, hemicellulose, lignin and pectin.

Lorna Gibson, the Matoula S. Salapatas Professor of Materials Science and Engineering at MIT, says understanding plants' microscopic organization may help engineers design new, bio-inspired materials.

''If you look at engineering materials, we have lots of different types, thousands of materials that have more or less the same range of properties as plants,'' Gibson says. ''But here the plants are, doing it arranging just four basic constituents. So maybe there's something you can learn about the design of engineered materials.''

A paper detailing Gibson's findings has been published this month in the Journal of the Royal Society Interface.

To Gibson, a cell wall's components bear a close resemblance to certain man-made materials. For example, cellulose, hemicellulose and lignin can be as stiff and strong as manufactured polymers. A plant's cellular arrangement can also have engineering parallels: cells in woods, for instance, are aligned, similar to engineering honeycombs, while polyhedral cell configurations, such as those found in apples, resemble some industrial foams.