27 August 2015

Urgent Need for Native Plants - Doug Tallamy

Doug Tallamy packs auditoriums everywhere he speaks and last week he had a crowd of 250 with standing room only at the Tulsa Garden Center.

Tallamy is America’s hero of the movement to save humans by restoring the natural food web, one back yard garden, public space and corporate green space at a time.

Dozens of research studies have pointed to the emotional and physical health benefits of plant corridors over mowed spaces but Tallamy’s knowledge and passion push participants to feel an urgency to make a commitment, no matter how small. 

Whether you have some control over a public area or a residential neighborhood space, Tallamy suggests that you select plants that support and improve life.

The building blocks of habitat are bunching grasses instead of lawn grasses that need to be mowed, shrubbery that wildlife can use rather than useless ones, and beneficial canopy and understory trees. 

Every patio, front yard, park, fence line and community can begin to create food web friendly habitats.

Insects and plants have co-evolved to have a mutually beneficial arrangement so that now ninety percent of all insects can raise their young only on specific plants. Imported, European and Asian plants are alien to native insects and other wildlife.

By estimate, there are 45-million acres of lawn being sprayed and mowed; none of it provides food for wildlife

Why should you care enough to plant habitat where you once grew lawn?  Two examples: There are only 3% as many Monarch butterflies as there were 30 years ago and 50% fewer songbirds than there were 40 years ago.

Plants and animals in the food-web are the building blocks and rivets of life as we know it. When 
animals face reduced bio-diversity, humans also face reduced conditions because plants and animals create the clean water, oxygen, pest control and pollination that we need to survive.

Some of the landscape plants to avoid: Ginko biloba trees, Crape myrtle shrubs, Euonymous burning bush, Chinese wisteria, Japanese mimosa, Russian olive, Bradford pear and Chinese photinia. None of these imports provide any benefit to the food web, and there are over 3,000 of them being promoted to gardeners.

All varieties of oak trees help the food web, giving food and shelter to over 500 insect species. Those insects in turn feed birds, control garden pests, and pollinate fruits, vegetables and flowers.

Tallamy’s underlying message is to plant more insect food. One example he gave is that Ginko trees support 3 insects while native Prunus (plum and cherry) trees and shrubs support 500 insect varieties.

Clean farming methods use pesticides and herbicides to produce the most food. In the process, native plant green belts have been lost. Since that probably will not change soon enough in any significant way, public spaces and our gardens are all that’s left for the natural world, according to Tallamy.

When talking about the need for natives, Tallamy pointed out that Asian imports often leaf out earlier in the spring. If you think of a plant’s leaves as its mouth for collecting sun, this small difference means that food web plants do not have a chance to achieve spring growth before they are covered up.

“Bringing Nature Home”, Tallamy’s 2007 book (www.bringingnaturehome.net), has charts of plants that best support the food web. The US Forest Service provided funding for his office to create a list of the most beneficial plants for every county in the country. It will be available Jan 2016 on the National Wildlife Federation website at www.nwf.org.

Video of Tallamy’s 2015 presentation http://hort.li/1GDw

Tallamy's plant list by region is at http://udel.edu/~dtallamy/new_xls/webplants.xls


While there is no call to tear out your existing shrubs and lawn, there is an urgency to put in native plants among them. For regional suggestions visit Oklahoma Native Plant Society http://www.oknativeplants.org/

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