Garden Weed With A Bad Reputation

star thistle.jpg

Don’t let yellow start thistle get a start in your garden!  It can appear without warning to gain a foot hold, particularly in suburban and rural homesites. This painfully prickly plant has already earned a very bad reputation among ranchers who have watched it damage valuable range land.  This imported annual thistle was first brought to America in animal feed and ship’s ballast.   Perfectly adapted to dry conditions of the west it naturalized her and is proving more vigorous than grasses, native and exotic.  But what ranchers really dread is the wounds to their livestock as they try and forage among the wickedly sharp spined plants.  There is even a disorder caused by accidental ingestion of star thistle.  It’s a real planta non grata! While commuting through farmland everyday for years, I watched a two acre pasture become incrementally infested with star thistle.  It marched across the grassland in just a few years to completely dominate the area.  So when a load of manure was delivered followed by an outbreak of star thistle on my property, I wasted no time in controlling it.  My preference was to keep a sharp eye out for the blue-grey coloring of the seedlings and pull them roots and all.  I never mowed a fully flowered star thistle for fear I’d help it spread its seed.  Plus, it’s the flower head that produces the spines. The USDA produces a great deal of useful information on star thistle eradication on a large and small scale.  It’s no easy task.  My advice is to watch your land and garden closely in the summer for signs of this heat loving weed, and rip them out immediately before seed sets to inundate you next year. Click here for USDA information on star thistle: http://www.invasivespeciesinfo.gov/plants/yellowstar.shtml