If a flower contains both male and female reproductive parts, as some flowers do, it is said to be a perfect flower. Flowers that lack one of the reproductive structures, either the stamens or pistils, are known as imperfect flowers. An imperfect flower is also therefore, by definition, incomplete.
Some plants have just one flower; these are called solitary flowers. Others produce clusters of flowers. Scientists first thought flowers bloomed based on their exposure to light. Later they discovered that it’s not the light, but the uninterrupted darkness that triggers flowering – giving us the classification of short day, long day, or day-neutral plants. Day-neutral plants are indifferent to uninterrupted darkness. But some plants, petunias for example, don’t really fit any category because they’ll bloom in all different combinations of day lengths.
A lecture on botany in week two of Master Gardening school queued up a lecture the following week on diseases. Inga, our local expert on the topic, warned that most students wonder how plants survive at all after learning of all the diseases to which they may succumb. I was among them.
Inga made the point early on in her lecture that to identify a plant problem, you must first know what a healthy plant looks like. Some plant’s normal characteristics, or habits at certain stages of growth, can be similar to the symptoms of a disease. Diseases and symptoms of disease are plentiful nonetheless, including leaf spots, fruit rots, blights, fungi, too much moisture, not enough moisture, bacteria, viruses, the dreaded nematodes (tiny roundworms), and even mistletoe. On this note, Inga reminded us that although some diseases cause symptoms and the plant may not look perfect, not all diseases kill. You have to decide what you’re willing to tolerate in terms of appearance.
The lecture on disease was a natural segue to insects. Sam, who has his master’s degree in entomology, and proud owner of an insect collection, had more first-hand knowledge of bugs than I ever imagined possible. Of course, his first point was to remind us that just as soil is not called dirt, real gardeners know that insects are not bugs – although there are a few exceptions, naturally.
For every pound of human on earth, I have now learned there are approximately 300 pounds of insects. They thrive in more environments than any other group of animals, and they are among the oldest animals on earth. They live in the air, in the water, on top of the soil, and in the soil. There’s an estimated 100,000 different insect species in North America alone. By some estimates there are 10 quintillion (10,000,000,000,000,000,000) individual insects on earth at any given time; a typical backyard contains 1,000 or more different species. I wish I didn’t know this.
Even so, the vast majority are harmless or even beneficial; less than 1% are considered pests. That sounds encouraging unless the 1,000 in your backyard are all part of that 1%. That’s highly unlikely in reality since pests have natural enemies, and the beneficial species help control at least some of the worst pests. In fact, insects and weeds are part of a natural ecosystem.
If you plant a garden or establish a grassy lawn, the natural process begins to re-establish a balance of native and non-native plants. The weed that takes hold in the lawn is the first stage in a sequence of events that, if allowed to continue, could eventually result in a forest. Cultivated plants are not nearly as competitive as our native plants, weeds and insects; cultivated plants survive only with the constant help and intervention of the gardener.
The wheel bug is the largest of the 150 or so species of assassin bugs, a predatory insect of great benefit to gardeners. (Photo by William Johnson)
Master Gardeners are taught that it’s not possible or even desireable to rid the garden of all pests. The best way to control the over-population of pests is to keep your plants healthy and reduce plant stress. Healthy plants tend to resist infestations by pests while plants with low vigor actually attract pests.
Remember, however, in a true ecosystem there is no such thing as pests. Only humans consider something a pest when it occurs where they are not wanted.
We’re taught to visit our gardens regularly to observe what’s going on. Know what to look for and intervene early with a strategy that’s economical, physically feasible, effective, and the least toxic.
If all this is true of plants, maybe it’s also true of humans.
Sometimes we prefer a solitary life while others prefer clusters of friends. There are morning people, night owls, and workaholics. Some folks don’t really fit any category because they’ll bloom no matter what their environment. We’re all vulnerable to disease from time to time, although much less so if we are healthy and stress-free. And an uninterrupted, good night’s sleep goes a long way to help us rejuvenate and produce our best blooms.
Sometimes our gardens seem to have been invaded by pests that threaten the balance of our environment. But what we call “pests” are actually part of a natural system at work. An ecosystem has no pests. Only humans consider something a pest when it occurs where they are not wanted.
Some of us are more competitive while others will require the constant help and intervention of a gardener. No human is perfect, and therefore, by definition, incomplete. The famous line, you complete me, comes to mind.
History suggests the best way to maintain a healthy ecosystem is to check in with each other regularly to observe what’s going on. Know what to look for and intervene early with a strategy that’s economical, physically feasible, effective, and the least toxic to each other – and our planet.
Test your knowledge:
Plants are categorized by their growth habits. These include:
A. Shrubs, trees, and ground covers;
B. Evergreen and herbaceous;
C. Annuals, biennials and perennials;
D. Monocots and dicots.
True or False: Fungicides kill fungi.
Which of the statements below is false?
A. It’s not possible (or even desirable) to rid gardens of all pests.
B. When you see a plant problem, the first thing to do is spray it according to the label
C. Prevention is the first tool in pest management.
D. Misuse of pesticides can result in the pest evolving a resistance to that particular chemical.
E. All of the above statements are true.
True or False: The vast majority (>99%) of insects are considered harmless or beneficial.
C. Annuals, biennials and perennials;
False: Fungicides slow down or prevent fungus attack; they do not kill the fungus directly.
B. When you see a plant problem, the first thing to do is spray it according to the label instructions. False: the first step is to identify the plant.