Two Alien Thistles

     Two kinds of thistles, nodding and Canada, commonly bloom in June in pastures and abandoned fields, and along raodsides in Lancaster County, Pennsylvania, as elsewhere in North America.  Nodding thistles live  from the St.Lawrence River to Maryland and Canada thistles can be found throughout much of the United States.  Both these species, however, are originally from Europe.
     Though these thistles have attractive flowers and benefit certain species of wildlife, most people don't like them because they are invasive.  Canada thistles really spread, but the nodding not as much.
     Nodding thistles can grow up to four feet tall and each plant develops two or three strikingly hot-pink blossoms, each of which is about an inch and a half across and quite decorative.  Those large, heavy blooms nod in the wind, hence the plant's name.  This type of thistle also has spiny leaves that protect the species from foraging animals, and cause people pain when those persons touch that foliage.
     Canada thistles stand up to five feet tall, have a few stems on each plant and several blossoms clustered at the top of each stem.  Each bloom is about a half inch across, has a sweet scent and is pale-lilac in color.  Those flowers also attract many insects of several kinds; insects that are interested in sipping the flowers' sugary nectar, pollinating them in the process.  This species also produces dense stands of itself that offers cover for small wildlife.  And its soft, light-brown fluff, that is designed to carry the seeds away on the wind, which would spread the species, floats on the wind when birds harvest the seeds from that down.  But Canada thistles, like most kinds of life, reproduce far more than is necessary, which makes up for losses. 
     American goldfinches, house finches, song sparrows and other kinds of seed-eating birds, and mice, ingest thistle seeds in July and later, adding more beauty and interest to the plants and the habitats that harbor them.  Goldfinches actually don't even nest until July so they can line their beautiful, dainty nurseries with thistle down and feed predigested thistle seeds to their young.
     Though alien and invasive in North America, these thistle flowers are pretty to see, and those blooms and their seeds benefit wildlife.  Sometimes it's difficult to decide whether to control these thistle species or simply enjoy them.  But for certain, they are here in North America to stay.