Aug. 17, 2007 — Most cacti appear to be leafless, but a new study has determined that all of these often prickly plants actually do possess ultra tiny leaves.
The findings, published in the latest International Journal of Plant Sciences, not only add to the fascination surrounding these already unusual plants, but they also may broaden the known functions of leaves.
For curious cacti owners desiring a glimpse of the leaves, caution is advised.
"If people do look closely at their cacti trying to see leaves, they need to be careful of spines close to their eyes," James Mauseth, the paper’s author, warned.
Mauseth, a professor of biological sciences at the University of Austin at Texas, explained to Discovery News that the newly found leaves — best viewed under a microscope — exist at the base of spine clusters.
He made the determination after gathering samples of 147 different cacti species, most of which he obtained in the wild. Mauseth then conducted extensive analysis of the plants and their tissues under high magnification.
While the leaves "had more or less normal morphology," almost all were missing blades. Just over half had xylem, a tissue that conducts water and nutrients from the roots up through the plant, but no cacti leaf analyzed had just phloem, which is a food-conducting tissue.
Leaf sizes ranged from 30 to 2310 micrometers. A single micrometer is equal to one millionth of a meter or just .00003937 inch, so the documented cactus leaves may very well be the world’s smallest.
By visiting this site, you agree to the terms and conditions
of our Visitor Agreement. Please read. Privacy Policy.
ATTENTION! We recently updated our privacy policy. The changes are effective as of September 10, 2008.
To see the new policy, click here. Questions? See the policy for the contact information.
