No greater loss can be cited than that of the wild form of honey locust with its starburst bundles of branching thorns, each one needle-sharp and often eight or more inches long. These amazing trees have not been planted in decades it seems, replaced by thornless cultivars with leaves of chartreuse and maroon hues. The colors are nice but the new locusts are sad and wimpy without their jabbing defenses.
In patrolling the neighborhood for subjects to illustrate this article, I drove straight to the source, the holy grail of crowning thorns - a wild-type honey locust at the corner of Houst's storage barn in Woodstock. The tree was still there, but as happens from time to time the mystery clipper of thorns had been there, and there were no prickers within reach. I was cheered within minutes to find a young locust sporting spines to spare. The little tree, hiding behind a tough-looking Callery pear, raised no objection to my clipping a couple of its shining maroon projections for show-and-tell.
Along wilder byways branches and twigs proved pointless save for the ubiquitous multiflora rose, an introduced thorn-bearer once promoted by the USDA as a hedgerow in cow pastures so the cows couldn't chew down the hedges. It's since become a notorious pest, as has the pin-prickly barberry shrub brought in as an ornamental and sheep pen hedge. Both the rose and the barberry invade woods, as long as there's a little sunlight.
But where were the native thorn bushes? I finally found some in a decidedly disturbed habitat, a power line cut. Here were several kinds of brambles, the bearers of blackberries and raspberries. Like multiflora rose they grow long whips lined with sharp points that catch and rip and scratch. These native shrubs and trailers need sun, and do poorly in forest shade. There were plenty under the high wires, but I was hoping for a non-native to add visual variety - the wineberry, a European raspberry introduced farther south in the Hudson Valley. As the name suggests, its purpose was for making wine, but that never worked out. The berries are tasty, but a bit furry. In keeping with this fuzziness the twigs are bristly. Perhaps it isn't to be found this far north. I have seen it in Kingston, though.
The long and winding descent of Hommelville Road sent me across NYS Route 32, over the Thruway and north into the Kalkberg limestone flats where the pickings were not much better but were at least different. Old hedgerows between former fields still harbored the singularly uncommon prickly ash, resembling an ash but in fact the sole citrus species native to the northeast. Its squat spines are nonetheless as sharp as any. Prickly ash has the further distinction of hosting the caterpillars of the giant swallowtail when this mega-butterfly of the deep south occasionally wanders north on hurricane winds. Down south the females lay eggs on lemons, oranges and their relatives, but here there's only prickly ash, and it'll do in a pinch.
The pinnacle of spinous refinement may be represented best by the hawthorns. Straight, stiff and narrow beyond any others, hawthorn spines are simply perfect, the epitome of thornhood. The astonishing variety of them - over 100 species in North America - suggests an evolutionary explosion in this single genus. Yet I failed to find a single hawthorn in an afternoon's search of local country roads. Where are they? Apparently people used to plant them more often, as I saw many beautifully flowering hawthorn trees when I was growing up in northeastern Ohio.
Hawthorns, spiny honey locusts and other armed trees and shrubs have fallen out of favor.
Apparently there is also a scarcity of spines and stickers in the wild that can't be explained by domestic breeding to eliminate undesirable features. It may be that producing these extras is expensive. Spines are not simply branches that taper, or buds that make stiff pins instead of leaves or flowers. Thorns are not reproductive. They are much tougher and denser than ordinary wood, and structured differently. It's hard to grow cells densely and to a sharp point.
If you don't really need spines why bother having them? An obvious explanation is defense against herbivores. Heavy browsing will put enough pressure on some plants to select for more discouraging defenses. Another function, apparent in spiny vines such as catbrier, is added support for gangly, twining plants. As a catbrier vine branches and stretches, the prickles grab other vining branches and also twigs of shrubs, holding the tangle together. Such structural support may also work well for thickets of small shrubs, acting as a windbrake. Again, natural selection may favor spines on certain vines.
I ask myself why I like thorniness, and I'll try to explain. To me it represents the natural way of things in distinction to the artificial way - that is, our way. Organisms and their attributes appear by virtue of complex, chaotic processes free of intentional manipulation driven by likes and dislikes. People are driven by their likes and dislikes to manipulate and alter nature. But peoples' likes and dislikes are determined by what? Who knows? I trust nature much more than I trust people. Why? I think I could explain but maybe some other time. ++
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