In any ecosystem found on this beautiful planet there are plants that have evolved to be survivors. These plants define resilience. And they usually hold a place in their ecosystem that may be the missing puzzle piece to survival for not only themselves but others dependent on them when times get tough.
Perhaps the best example of this resilience, the ability to emerge when all hope may be lost. This is a common trait for plants that are included in the genus Rubus. These members of the Rosacea family are the many thorny plants that include blackberries, raspberries, dewberries, and hundreds of other species all included within this subset of plants. In our region there are over 100 of these masters of survival; each using their own abilities to pass on the family genes. Throughout the world there are thousands of individual species included in this large plant group.
The most common of these plants is the blackberry; not that this is one species. In fact there are dozens of different blackberries that call our region home. The most common is the Allegheny blackberry (Rubus alleghaninsis) which dominates the plant community in many old fields and meadows. Most of us are familiar with the fruit. The fruit is actually a cluster of drupelets that form around fertilized ovules. These clusters are rich in complex sugars, vitamin C and other vitamins, protein, and a host of minerals. They are particularly rich in antioxidants ( anthocyanins, ellagic acid, and salicylic acid) which are particular effective in preventing and combating cancerous cells.
And most people who pick blackberries are well aware that these plants are covered with stout, sharp, thorns that can inflict pain on even those with the toughest skin. These prickers account for the common name “brambles” which for many creates a little message in the brain that says “Stay Out!”. These thorns are just one of many survival tools that blackberries employ. By preventing intrusion it guarantees that at least some of the berries will survive to help start a new generation. The thorns also make the plant a valuable host in the realm of wildlife habitat. These dense layers of sharp, pointy prickers create hiding places for small prey. Cottontail rabbits can easily negotiate paths in the dense thickets while a marauding red fox would certainly be weighed down by the dense thorns tangled in its fur and attached to heavy stalks firmly rooted in dense soils.
And while mentioning reproduction it would be remiss to fail mentioning that this plant has other remarkable reproduction skills. The first of which is its amazing ability to take advantage of time. The blackberry plant seems to be aware that all old fields will eventually mature and turn into woodlands. The blackberry will leave viable roots and seeds in the soil that can lay dormant for decades. If anyone has ever clear cut an area of forest only to return in a year and see the entire area covered with blackberries you have experienced this plants ferocious will to survive. Forests that are 100 years old have been cleared only to yield to complete cover by blackberries within a years time!
Blackberries are also capable of clonal reproduction by sending out roots to start new plants. The tall stalks also often arch over and root into the ground to spread the plant across the landscape. But brambles best form of reproduction is by apomixis. Through this process the plant forms new drupelets and seeds without fertilization. Of course all offspring are identical to the parent. And so it is not uncommon for an entire field of blackberry to have one genetic signature.
Growth in blackberries is also unique. The first year stem is called a primocane. It is a single stem with thorns and primary buds that yield five to seven leaflets. This primocane can grow to 3 meters (almost 10 feet) in length in a given year. During the second year the stem does not grow any larger but puts its energy into growing lateral buds that hold flowers. The lateral buds have smaller compound leaves that hold three to five leaflets. This second year growth is referred to as the floricane. It is the fruit producing cane. This growth pattern allows the plant to focus on size and strength the first year and reproduction the second year. It is an evolutionary development that has proved to be successful.
Not only are the fruit valued by many animals but the foliage is prized as well. Many different species of caterpillars are dependent on Rubus as a main source of food during development. And amongst larger beasts, the white tail deer finds the blackberry leaf to be perfect for their palette. Rabbits, voles, and field mice may all eat the thin bark on the blackberry cane particularly at levels beneath the snow where the small animals are slightly more safe from predation.
The Rubus genus also has an amazing aesthetic appeal. During the summer when the wind blows the white underneath of the leaves of some species of Rubus can expose themselves and create waves of silvery color change over the landscape. In winter fields the red stems of the blackberry cane with a back drop of white snow is breath taking. And it my mind’s eye, a woven basket filled with the purple fruit is a symbol of a good harvest and nutritious and delicious food; a beautiful site indeed. And the bluish purple color found on a raspberry stalk has no other rival. It is unique amongst the palette of colors.
As a field ecologist I have been tangled in these wonderful plants many times. They can scratch your skin ferociously, tear cotton fabric with ease, and leave thorns behind in thick pants legs that will work their way through any thread count and give you pain later on when you aren’t expecting it. But even given the difficulty that these plants may cause I am in awe of their resilience. Through the miracle of evolution they have found ways to carry on. Neither flood nor fire can defeat this plant. It is defiant of time and can carry on genetic codes after decades of dormancy. It does not need fertilization to create new generations; a single plant can create offspring. It defends its fruit from invaders. And it does all of this while serving as protector of some of our most precious small animals like quail and cottontail rabbit.
These plants, who some call brambles and others call pucker brush in disdain for their abilities to create pain, torture, and misery, might just be overlooked as not only being beneficial but a key and necessary part of our temperate ecosystem. Long after any of us are gone a plant will emerge that is genetically identical to one that your grandmother may have harvested a blackberry from some 70 years ago.
And that, my dear friends, is something that the human being just can’t do.
Originally written for the Heath Herald in January of 2013.