Friday, September 28, 2012

The plot thickens...... Impatiens glandulifera!

I began my Ecology course for students at Gorno -Altaisk State University by introducing a beautiful plant I had seen down by the river on my first run here in the City of Gorno.  In an earlier blog, I showed a picture of Impatiens glandulifera, commonly known as Himalayan Balsam, or Policemans Helmet, or

I began wondering if the plant was native to Russia, or the region where I had found it.  Then the dreaded thought came to me that perhaps this was even an invasive!!! I realized I had better check this out and began searching for research papers on the genus Impatiens in Asia and Europe. There were plenty of papers, especially from the British Isles.

Well, it turns out that this beautiful plant is NOT NATIVE to Russias far east. It is also NOT INVASIVE here. It is however one of the top ranked (worst) invasives in Britain!
What I find interesting is that it is native to India and the western Himalaya. In the Himalayas it is frost tolerant and lives at elevations between 2000 and 4000 meters (see image below).
In the other places where it has been spread (mostly by purchase of seeds - it's really pretty- and subsequent movement by explosive seed dispersal, often into the rivers along which it grows) it is found between latitudes of 30 and 64 N(Beerling and Perrins 1993) and may not be frost tolerant in these places. 
The current global distribution of I. glandulifera is: (Cockel and Tanner, 2011)

• Present in 27 European countries (DAISIE, 2010), where it is widespread in 18 and invasive in 12 countries (CABI, 2004).
• Invasive in 8 states in Canada (Clements et al., 2008).  In Canada it is found in Nova Scotia, southern New Brunswick, Quebec, Ontario
• Present, though not invasive, in New Zealand (Sykes, 1982).
• Present, though not invasive, in the Russian Far East (Markov et al., 1997).
While all of this information was interesting to me, this next part is what peaked my interest 

'Present in 11 states of the United States and invasive in 3 (USDA, 2010). '
It is naturalized in California, Oregon, Washington, Idaho, Montana, and also in the northeast and Michigan. In New England it is presently reported from Vermont, Massachusetts, Connecticut and Maine. and the USDA map shows it in New York   SOOOO ,,, that is pretty close to my home in the Adirondacks!  But I have never heard of it there, nor have I seen it. 

In the summer I work with the Watershed Stewardship Program and we are trained and work in education and the science of invasive species.. I had never heard of this plant as a local threat.. maybe it is not due to a lack of frost tolerance.   But, if it is frost tolerant,,, or as climate change warms our beautiful mountain home I think we could be in big trouble with this one.  The paragraph  below the image describes the habitat in which this plant establishes and the physiology that makes it successful.   The habitat is so like our wetland habitats -  and the characteristics of its reproduction etc, strike a bit of fear into my heart!!

Habitat: Impatiens glanduliferatolerates a wide variety of soil types, but requires high soil moisture. Policeman's helmet is partially shade tolerant, and is found in lowland, riparian areas which include moist forests, stream sides, and roadside thickets. Associated species in western Washington sites include: blackberries (Rubus spp), Japanese knotweed (Polygonum cuspidatum), elderberry (Sambucus racemosa), Spirea douglassi ssp douglassi, reed canarygrass (Phalaris arundinacea), willows (Salix spp.), and ivy (Hedera helix).

Growth and Development: An annual, I. glandulifera germinates in February to March. Roots develop 12 days after germination and photosynthesis begins in the leaves four weeks after germination. Flowers are present from June to October, with shaded environments producing later flowers. This annual species can reach ten feet tall, in shaded areas. Seed set occurs about 13 weeks after flowering. When the seed capsules are mature, they split along the five seams of the fused stamens, ejecting seeds for up to 20 feet. The seeds  (up to 800 seeds per plant). travel along waterways, and they can germinate under water. The seeds are viable for 18 months, or more. The seeds do require cold stratification to break dormancy (Mumford 1988). I. glandulifera is susceptible to frost, both in the early seedling stage and at the mature plant stage. Pollinators include several species of bees, ten moth species, and wasps (Mumford 1988; Beerling and Perrins 1993).

Below is the map of its distribution in the United States. This plant is listed as a noxious weed in Connecticut, Oregon and Washington.....On the map below you can see that it is found in New York, Vermont and Massachusetts...

I guess I'd like to know more about the frost tolerance or lack thereof.  Does anyone know anymore about this plant and its level of threat to the Adirondacks? There are so many habitats that would be suitable and the seeds are larger and plants more robust than our native spotted touch-me-not. 


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