A Very Prickly Subject, Nature's Barbed Wire

At the beginning of November I began a series of posts with "A Brief Introduction to a Very Thorny Subject." Briefly, a true thorn is a sharp pointed modified branch, a spine is a sharp pointed modified leaf and a prickle is a sharp pointed outgrowth of the epidermal layer of the stem.

Since prickles grow from the surface of the stem and don't have a deeper connecting tissue as do spines and thorns, they can be broken off the stem with relative ease by (carefully) pushing them from the side. The brown patches on the stem in the third photo below are where prickles have broken off revealing the deeper layer of tissue inside the stem.

Probably the best known plant with prickles is the rose bush in the Genus Rosa, Family Rosaceae. Technically, all roses are thornless, but that doesn't mean a prickle won't leave any less a lasting impression. Dewberries and blackberries in the Genus Rubus, Family Rosaceae are also fairly well known for their prickles, especially by those who have gathered the berries.

Then there is "nature's barbed wire." Anyone who has tried to walk through a Texas woodland where Greenbrier, also known as Catbrier, is growing, knows the origin of the name nature's barbed wire. It is just about impossible to walk through a thicket of Greenbrier without a machete or shears and come out the other side unscathed:

Greenbrier berries do serve as an important food source for many birds and small mammals. Greenbrier thickets also provides excellent cover for many small animals. The tender new growth of the Greenbrier is frequently used to make a high vitamin C tea and as a salad ingredient. The older leaves become tough and bitter.

This set of photographs was taken along the Rio Medina Trail at the Medina River Natural Area on Tuesday, November 19, 2013