One of the last big flower shows each year is provided by the goldenrods. Within Kansas 12 species are known with several varieties. They are all perennials with large clusters of small yellow flowers that appear from the end of summer until frost. The leaves of goldenrods are simple, lance or egg shaped and usually have a toothed margin. Most species propagate by a spreading root system in addition to seed. They can be a troublesome addition to a wildflower garden for that reason. They become more common in pastures under heavy grazing pressure and so are used as an indicator species by range managers.
Goldenrod gets mistakenly blamed for the agonies of hay fever sufferers in autumn. It blooms at the same time as ragweeds (Ambrosia sp.), which are the real culprit. Ragweeds are pollinated by the wind. Using the wind to fertilize your flowers is a very chancy business. Only by releasing billions of pollen grains into the wind can they ensure that some will find their way to the female flower of another ragweed plant and produce seed. Because they are not pollinated by insects, ragweed does not need visually attractive flower parts. They are an inconspicuous green color. People suffering from allergies in September look for a flower to blame and goldenrod gets the rap because it is so visible and abundant. The pollen grains of goldenrod, as is true of all insect-pollinated flowers, are comparatively fat and sticky so that they will adhere to visiting insects and be transferred by them to another flower. In order for a person to be affected by goldenrod pollen, they would have to stick their nose right into the flower just like a bee would!
A casual observer will notice swollen lumps on the stems of goldenrods. Some will be round and others will be spindle-shaped. These are called galls and they are the homes of two different types of insects that are parasites on the goldenrod. Gall-making insects may be found on a wide variety of plants, but each species of insect is specific to a given species of plant and their galls have a characteristic and recognizable shape and location. The insect larva receives protection from most predators by living within the gall and it uses the inside of the gall for food.
The yellow of goldenrod makes a pleasant scene with the varied bronzes, russets, oranges and purples of the fall prairie. It is a sure sign that the first frosts of winter are not long away.
- This page was spun by Jim Mason -
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