Tumble weeds

http://www.weather.com/news/colorado-tumbleweeds-cover-homes-20140320

These tumbleweeds are trapping people in their homes, forcing some to call 911 just to get out of their own front door, according to a KDVR report.

For many people around the world tumbleweeds are iconic of the American west but they don't know how big this problem is 

Hi Muriel,

I didn't read the article corresponding to the link you gave yet because I spent my whole day trekking (ie far from my computer) and I've to catch up with my mail and others.

Tumbleweeds are also in other states of the soutrh west of the US, not only Colorado.

The strange is that, as far as I know, tumbleweeds are not American plants but they came from Russia (with Russian immigrants).
I don't understand why American people complain. Yes it's a problem but everyone has to deal with it: official services clean the public areas but individuals also have to clean their part. Yes it's complicated by the wind which blows the plants anywhere and in addition, these plants (which live a year only) are highly flammable.

Good luck Gérard for all your work and thank you for explaining the tumble weeds and also where they come from.