Hybrid plants and the environment
Ancient wisdom, modern gardens
"Consider the wildflowers . . .King Solomon in all his glory was not arrayed like one of these." The Gospel of St. Luke
In today's aggressive marketing climate, Jesus' thought-provoking words are even more apt than at any time since he first spoke them two thousand years ago. Pausing awhile to "consider the wildflowers", allows the inner eye to see, maybe for the first time, their often understated beauty. And once that awakening occurs, the appeal of exotic imports, "new releases" and artificial hybrids quickly fades.
In his posthumously published La Botanique, Jean-Jacques Rousseau [1712–1778] dismisses hybrid plants with enlarged or double flowers, as "nature disfigured by man". "Waste no time examining them", he cautions. "Nature is no longer there; she refuses to be reproduced by such deformed monsters."
The great landscape architect Sylvia Crowe, in her classic Garden Design, reaches much the same conclusion: "One of the more subtle qualities of plants is a certain relationship in colour and proportion between the stem, the leaves and the flowers, and the poise of the flowers upon their stems. It is these qualities which give the plant species a grace often lacking in the garden hybrids . . . . . The intensifying of flower colours by hybridisation can also throw out the subtle harmony of the wild plant."
The selective breeding of hybrid plants with enlarged or double flowers reduces or obliterates the stamen, the protein-rich, pollen-producing part of the flower, rendering the plant sterile and of little or no food value to honeyeaters [nectar-feeding birds]. If nectar is present, pollinating insects may be unable to reach it, rendering the plant of little or no value to pollinating insects and insectivorous birds. Hybrid native plants with oversize flowers and extended flowering seasons, grevilleas in particular, attract territorial, sedentary nectar feeders such as the Wattlebird and Noisy Miner that are not endangered and that drive out smaller, more vulnerable birds such as the Fairy Wren, Thornbill, Robin and many others that now face serious decline or extinction. Rousseau wasn’t entirely correct: A minority of hybrids do produce pollen, and these pose a further threat to the environment: Birds that feed on them may pollinate local native species, thus polluting the local gene pool. In a recent instance, CSIRO scientists discovered the rare Grevillea iaspicula and its habitat contaminated by nursery-bred hybrid grevilleas.
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