(This Buffalo News column was first published on September 11, 1995.)
It is not only the dip in temperature that signals autumn across the middle latitudes of North America. It is also our lovely fields of burnished gold.
Goldenrod is at once the most widespread, the most noticeable, and the most misunderstood of our fall wildflowers. A perennial, it rarely invades cultivated fields, but few waste places, marsh margins, open areas in woodlots, or early succession fallow lands escape its attention. There its lovely fronds or racemes or umbels or plumes, depending on the species, attract honeybees and bumblebees, syrphid flies and treehoppers, as well as soldier and long-horned beetles to its sweet nectar and sticky pollen. These in turn attract predators: ambush bugs, wasps, crab spiders, and what is to me that scariest of all insects, the praying mantis. The mantis finds this wildflower so hospitable that it often forms its egg cases on goldenrod stems. Meanwhile the goldenrod defends against the depredations of a moth and several small flies or midges by forming growths called galls. Most noticeable are spherical galls on stems, but there are also blister galls on leaves and bunch galls among the flowers themselves.
Examine the individual florets of goldenrod and you will find two types. Those nearest the ends of the fronds are female. Only the flowers of the central disk include male stamens as well. An arriving bumblebee can deposit pollen on the ray flowers before clambering on to seek the nectar of those in the center. Unlike most plants the spike-shaped goldenrods bloom from top down, perhaps because in early fall they have more competition with late-summer flowers in tempting insects. Then they entice these pollinators with their tallest tassels. Later that won't be so important: they will be among the few flowers remaining.
Goldenrods not only reproduce by insect pollination, their roots form rhizomes, bulb-like enlargements that are actually underground stems, from which grow clones of the original plant. Left to their own devices such plants form dense circular patches and, when the earliest central plants die to be replaced by other wildflowers, they form what botanists call a fairy ring. One of the loveliest fall sights is a fairy ring with the purple of asters or teasels encircled by a broad border of goldenrod yellow.
One way that the goldenrod does not reproduce is by airborne pollination. Like other insect-pollinated wildflowers, its pollen is heavy. Very few of the microspores that cause so much suffering to those susceptible to hay fever -- a remarkable misnomer for it is neither hay-related nor a fever -- are those of goldenrod. The real culprit is its common but little noticed neighbor, ragweed. For too long has goldenrod shouldered the blame for this affliction. It did not prevent two states, Kentucky and Nebraska, from choosing the goldenrod as their state flower, but it may have thwarted its choice as our nation's flower when this idea was widely supported a hundred years ago.
In All About Weeds, Edwin Rollin Spencer begins his account: "He is blind indeed who does not know goldenrod, but he is a taxonomist if he knows all the goldenrods." How true. About 20 goldenrod species are found in this region alone. Take into account hybridization and different-appearing forms of the same species and identification problems certainly do mount to punishing levels.
When goldenrods finally turn brown at autumn's end, their seeds are ready for distribution. Like those of dandelions, each has a number of tiny filaments attached to one end. They act as wings to carry off this diminutive embryo in the very winds that will so soon bring winter.-- Gerry Rising