Native plants tie your landscape into the local ecosystem through long evolved interrelationships. Exotic and nonindigenous plants lack interrelationships with the surrounding ecosystem, and therefore lack wildlife value.
Native plants can be used to fulfill the same human needs as exotic plants in landscapes. Ricke Darke, a leading native plant advocate, describes human oriented functions required of a landscape as follows:
- create living spaces suitable for play, meals, and entertaining
- add beauty and sensual pleasure including color and fragrance, framing, and order
- offer shelter and refuge, privacy and screening
- yield sustenance through edible plantings
- produce opportunities for storytelling and other artistic expression
- inspire and educate by providing exposure to or immersion in natural phenomena including seasonal cycles, cycles of plant and animal growth and migration
In addition to serving the human oriented needs within a landscape Native plants serve the ecological needs of wildlife, a function exotic plants are unable to perform.
Many of the ecological functions native plants perform go unnoticed to the casual observer. In 2007 Doug Tallamy’s book Bringing Nature Home explained for the first time how native plants foster biodiversity within a landscape. Using the insect order Lepidoptera (Butterflies and Moths), Tallamy explains their long evolved interrelationship with native plants. Each species of butterfly and moth require specific host plants to lay their eggs. Why? Because caterpillars just can’t eat whatever plant they want. Each individual species of Butterfly and moth caterpillar only has digestive enzymes that are able to break down the foliage of one-several species of host plants. Monarchs are a well know example that can solely eat milkweed plants. Without milkweed monarchs would cease to exist.
More obvious ecological services native plants offer to wildlife, include nectar rich flowers for butterflies and hummingbirds. Plant the correct native plants in your landscape and you can attract wildlife that is far more beautiful than any plant or flower. Dozens of flamboyantly colored songbirds only frequent landscapes with diverse native plantings. Baltimore orioles, Scarlet Tanagers, Eastern Bluebirds, and Yellow Warblers are a few examples. Landscapes dominated by non-indigenous plants don’t support the insects they need to feed themselves and their young. So, you want me to attract more insects to my landscape?
Yes, 80% of the worlds animals are insects, 99% of them are beneficial or benign. The benign ones go mostly unnoticed by humans. The beneficial ones are pollinators needed to produce many of the foods we eat. Others decompose organic waste for us. Without them we would all eventually have dead stuff and poop towering over our heads. Some directly produce products we use such as silk, wax, honey shellac, and certain medicines. Ever enjoyed a delicious organic all natural food product that was red. Carmine, cochineal, or natural red 4 is an all natural red food coloring found in yogurts, juice drinks, cosmetics, and red candy. It’s actually a sundried crushed beetle from South America. But the bugs are better than the alternatives such are Red No. 2 or Red No. 40 which are synthetic and made from coal and petroleum by products.
Other beneficial insects eat harmful insects. Harmful insects though only make up 1% of the entire bug population, however they are the first image we think of when the word insect is mentioned. Negative experiences stand out in our brains. These one percenters bite us, feed on our pets, cause economic damage, and make us sick. Mosquitos, ticks, lice, fleas, knats, termites, aphids, and Japanese Beetles. Their names alone make us cringe. However it’s important to recognize landscapes consisting predominately of Native plants will not have more of these harmful insects. Native plants do not attract them any more than non-native plants. Native plants do however support denser populations of beneficial insects, and attractive songbirds who eat these harmful pest for you.