Biodiversity is a hot topic right now. It is sometimes used interchangeably with species diversity, but they mean different things. Native plants are important for both species diversity and biodiversity.
Species Diversity
Species diversity is the number of different species in a given area. Since plants and animals are inter-related, species diversity can serve as an index of the ecology in a given area.
Biodiversity
Biodiversity encompasses species diversity but goes farther. Not only are the number of species in a given area important, but how genetically diverse these species are matters. Zoos try to breed their animals while preserving as much genetic diversity as possible in a limited population. Accredited zoos often trade animals to make sure inbreeding will not weaken the species.
Why Diversity Matters
Both the sheer number of species in a given area and the genetic diversity are important. As plants and animals decrease or become extinct, their role in the ecology of the area they disappear from is empty. For example, if an insect becomes scarce, the animals that evolved to eat that insect don't have as much food. Now the animals decline because they can't raise their babies without the insect protein that has disappeared. These absences ripple up the food chain until they hit humans, too.
The genetic diversity of a species in a given area matters, too. When populations are isolated, the genetic diversity drops. Eventually, the isolated wildlife may evolve into another species, as in the Galapagos Islands. Sometimes, though, the animals become too closely related. They start having more health problems and more problems raising their young. If additional unrelated members of that species are not introduced to increase the genetic diversity the species may fade away and become extinct.
Best Native Plants For Bio-Diversity & Conservation
The Irish Potato Famine, which killed millions of Irish people and led millions of Irish to leave Ireland and come to the United States and other countries, is an example of what can happen if genetic diversity drops below a certain point. The Irish started growing potatoes as food for themselves and as food for their English landlords. They grew one specific variety of potato. A disease these particular potatoes were vulnerable to spread across Ireland. It caused the potatoes to become a stinking mess of slime when stored.
There were potato varieties resistant to potato blight. They just were not the ones given to the Irish to grow. Monocropping, or only growing one type of one crop, leaves everyone vulnerable to diseases that strike the variety planted. If, however, several different varieties of a plant are grown, there will still be food if disease strikes one variety.
For example, a scientist spent his life traveling around the world and collecting all the kinds of wheat he could find. He preserved the seeds. Because the planet is hotter now, some types of wheat are not producing as much. However, scientists are now sequencing the genes of all the kinds of wheat they have and think they have found some that will protect wheat from higher temperatures. Once a gene is lost, it is almost impossible to recreate it. With biodiversity, those genes remain available to solve new problems.
Using Native Plants Helps Biodiversity
Using the plants native to your region helps produce more plants that can feed more of the animals that eat them. People who grow vegetables now frequently place flowers to attract pollinators so the pollinators will pollinate their gardens. Using native plants to do this makes plants the area's pollinators can use more available.
People who love a nicely landscaped yard can grow native ornamental plants that will help the native animals and birds grow. If everyone yanked one non-native species from their yard and planted one native species, the biodiversity of the area would soar.
Many people plant milkweed for Monarch butterflies to lay their eggs on. These milkweed plants create a bridge between parks and other wild areas so the Monarch butterflies can safely make their migration without their larva starving.
Doug Talley, an entomologist, has expanded this concept to ask people to grow native species in their yards so they become a bridge for lots of animals and birds to use to find mates. Not only does this increase the biodiversity of urban areas, but it also helps animals to keep their genetic diversity up by providing a way for them to find other members of their species they are not related to when breeding.
Native Plants Are Tough
Native plants have evolved to grow in spite of pests and diseases that are common in their areas. They have also evolved to live with the area's rainfall and the soils that exist in that area. Native plants, once established, do not have to be watered unless there is a drought. They do not require as much fertilizer and don't need to be sprayed with as many pesticides.
Replace Non-Natives Gradually
Unless your house has just been built, you probably have a landscape full of plants. You don't have to rip it all out and plants natives all at once. As plants die or you just want a change, you can use native plants to fill those spots. Gradually changing your landscape is an affordable means to replant with native plants.
Of course, if you want to rip everything out and start over, we will support you in that. Some places that are having water shortages are paying people to remove water hogging lawns and non-native plants, so check with your city and county water district to see if they will reimburse you. You could get a new landscape and a lower water bill.
We Can Guide You
Of course, you have to find out what plants are native to your area. Garden Plants Nursery can help guide you when selecting the plants for your landscape. Our gardeners can tell you what grows best in your area. We can advise you on plants for the sun and plants for the shade, so if you need the perfect plant for a special spot in your garden, we can suggest a few to choose from. Simply give us a call or send us an email.