Seeds of destruction being spread through the county forest

Legislation being considered to control spread and sale of invasive species
By Kate Harries AWARE Simcoe April 15 2012
When people dump  garbage in the forest, it’s a nuisance.
When they dump leaf and yard waste in the forest, they may be sowing the seeds of destruction.
People imagine that their yard waste is organic and can’t do any harm, Simcoe County Forester Graeme Davis told a meeting on invasive alien plant species last week.
But the seeds of invasive garden plants are introduced through the waste and then spread through the forest, displacing native wildflowers like trilliums and killing soil organisms that native trees need to germinate.
“It’s more problematic than garbage, that we can pick up and remove,” Davis said, adding that in almost every case where an invasive species is found in the forest, county employees have been able to trace it back to illegally dumped yard waste.
Davis was one of five speakers at the AWARE Simcoe meeting on Saturday in Elmvale. About 130 people attended.
Each speaker stressed the magnitude of the problem, and the importance of halting the spread of invasive plants at the start, when the task is manageable and the cost is small – not once they are solidly established over a wide area.
“Ontario has a huge invasive plant problem,” said Erika Weisz, invasive species biologist with the Ontario ministry of natural resources. There are 417 invasive plants in this province, more than in any other jurisdiction in Canada.
“After habitat loss, this is the greatest threat globally to biodiversity,” she said.
She said the government has set up a centre to do research into invasive species In Sault Ste Marie, is stepping up efforts to educate the public (there’s a website: www.invadingspecies.com) and has set up an invasive species hotline: 1-800-563-7711.
Weisz was questioned by several people on why there is no legislation to require landowners, including governments, to control invasive species and to stop nurseries from selling them.
Legislation is being worked on, she said, but it’s not simple. “We’re talking about an industry here,” she said, and the problem is one of supply and demand. “If you stop buying, they’ll stop selling.”
Orillia environmental consultant Bob Bowles pointed the finger at gardeners as key vectors for many invasive species. Periwinkle and goutweed, both popular garden plants recommended as easy groundcover by the landscape industry, turn into huge, dense, spreading problems when they escape, crowding out native plants.
Invasive Norway Maple is often recommended as a shade tree, but our native Canadian species are both environmentally appropriate and beautiful. “Why not plant a Sugar Maple, they’re the best tree going,” he said.
The tall plumes of the Common Reed, or Phragmites, are a familiar sight along roads and highways. Some think them attractive, but for wildlife they spell disaster, spreading into wetlands and along beaches. “It’s completely locked out areas,” Bowles said of the reed. “Turtles can’t move through it, birds can’t nest in it – it’s a No Man’s Land.”
Bowles said the most dangerous plant in his opinion is Glossy Buckthorn. It is shade tolerant and forms dense thickets, crowding out woodland species. Birds eat the fruit – which gives them diarrhea – and spread the seed.  The related Common Buckthorn grows on dryer soils and is a primary host for the soybean aphid.
For Davis, the invasive that scares him the most is dog-strangling vine. “It jumped out three years ago,” in one location. Now, there are 15 known locations in Simcoe County.
Dave Featherstone of the Nottawasaga Valley Conservation Authority,  described how dog-strangling vine  has been found in one spot in the internationally recognized Minesing Swamp, and the county forestry department worked with the NVCA to spray the weed and hopefully eradicate it.
It doesn’t take long for dog strangling vine to get out of control, said Bowles, who in 2000 found and reported  two small patches on a trail leading to Barrie. It’s likely no action was taken because last year he checked the route and found solid dog-strangling vine along both sides of the trail. Sprayimg with a herbicide is the only effective control to date, Bowles said.
The sad thing about dog-strangling vine is that it presents a threat to the monarch butterfly, already beleaguered by loss of habitat, climate change and the dwindling space in which its host plants, the beautiful North American native milkweeds, are allowed to grow, or are planted. Dog-strangling  vine is a European member of the milkweed family and the monarchs are deceived into laying their eggs on the plant. Unfortunately, when the caterpillars emerge, they are unable to feed on the leaves and they die.
The seeds of invasive species hitch rides from infested woods in southern Ontario to pristine locations further north,  in the mud that sticks to recreational vehicles like ATVs or mountain bikes, or within the county on tree harvesting or ditch-clearing equipment… Or just on hikers’ boots and dogs’ coats.
We all have to become much more aware of the damage we are doing unwittingly, said Rachel Gagnon, of the Ontario Invasive Plant Council, which has a number of useful publications and conducts workshops for municipal employees and the public. “Spread the word, not the species.”
One local effort at fighting back against invasives is the Big Pull, the Tiny Marsh Garlic Mustard Eradication Days, set for Saturday and Sunday, June 9 and 10, and June 16 and 17, 9:30 am-noon. Volunteers are invited to come out for whichever morning suits them and spend some quiet time in a corner of the marsh where there has been an early-summer pull for the last three years, since garlic mustard was first spotted there. It’s estimated that it takes 10 years until the seed bank in the soil is exhausted. For more information call 705-322-2545.