The changeable life of Lance-leaf Greenbrier.

The greenbriers (Smilax) are infamously variable, but one species has what almost seems like a "larval" and "adult" form. Lance-leaf Greenbrier, Smilax smallii, grows primarily in woods. As a young plant (or what I assume is a young plant), it grows like a ground-cover low on the surface, with leaves designed to capture the minimal light that penetrates to the ground: large leaf surface, wide thin blades, and light color. I believe during its young years on the ground, it's storing up a large underground tuber. When the tuber reaches sufficient size, Smilax smallii sends up an amazing thick shoot that grows straight up, leafless but armed with prickles, toward the canopy. Once it encounters a branch it latches on with tendrils and then makes its way to the outer surface of the canopy, where it grows a dense covering of small, leathery, dark leaves, designed for high exposure.

One trail that I frequent has a large amount of Smilax smallii at ground level and in the canopy. Some canopy plants were recently felled in Hurricane Zeta. I took this opportunity to make observations to show the morphological variation.

(1) Ground-level S. smallii (large, triangular, variegated leaves with wavy margins; https://www.inaturalist.org/observations/156537778).

(2) Canopy-level (smaller, dark, lanceolate leaves, densely spaced; https://www.inaturalist.org/observations/102799377).

(3) The relatively rare intermediate low-climbing form (mid-size, slightly variegated, intermediate shape leaves; https://www.inaturalist.org/observations/68238365).

(4) Here is one of the spectacular "reachers" growing straight up from ground to canopy (https://www.inaturalist.org/observations/41900217).

(5) And here is an example of the massive underground tuber that Smilax smallii stores as it grows (https://www.inaturalist.org/observations/51459612)

Posted on April 18, 2021 01:39 AM by janetwright