Because you don't need to reseed it every year, as you would with annuals. Perennials come back after every growing season, or after every winter. Note that what is grown on lawns up north is different than what is grown down south.
Most of it is perrennial.
The most common vegetation in Winnipeg is probably the grass on peoples' lawns.
grass
The grass that grows on most lawns is a perennial. This is because it grows, reproduces, and flourishes over and over and it still stays on your lawn. An example to prove it is a perennial is that if you had a lawn full of green grass and about 2 years later it is still there then it is not a biennial, and if you had a lawn full of green grass and the growing season is over and it is still there then it is not an annual. The only choice left is a perennial.
cow eating grass
Green Green Grass of Home
Most lawns are composed of grass; anything other than grass is considered to be a weed. If you have planted flowers or decorative plants of any kind on the edge of the lawn, once again, anything other than what you planted would be considered to be a weed.
As of August 2014, the most popular sport shops in Australia include Medal Displays and Sportz Grass. Fun Sports is another popular choice.
a feild of grass whare they threw tomatoas at other people
Most likely the offenders are voles. They will destroy your lawn, and make trails thru the grass, but you will need a pro for this one, as you dont want to toss poison on your lawn where a pet or a kid could get at it.
A number of things humans can do return nitrogen to the soil. but I'm betting the most common one is mowing their lawns. The decomposing grass clippings will put some nitrogen back into the soil.
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