Lee Valley & Veritas

Gardening Newsletter
  Volume 10, Issue 8 - August 2015  
 
What Is It?
What Is It?
(Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org)
 
There's been a lot of talk lately about wild parsnip (Pastinaca sativa). This invasive plant, found throughout North America, grows densely and spreads prolifically. During much of the summer and early fall, it is one of the most visible yellow-flowered weeds found in roadside ditches, public recreation areas, around sports fields and along fence rows and railroad tracks. It can also sometimes be found on residential properties.

Harmful Effects
Contact with the plant's sap can cause the skin to become photosensitive in the area where exposure occurred. This can result in severe blistering after exposure to sunlight. If sap gets into the eyes, it can cause temporary or permanent blindness.
 
What Is It?   What Is It?
(Photo by Richard Old, XID Services, Inc., Bugwood.org)   (Photo by Ohio State Weed Lab Archive, The Ohio State University, Bugwood.org)
 
Plant Identification
The key to avoiding the harmful effects of this plant is to be able to identify it. This monocarpic (meaning it dies after bearing flowers and fruit only once) perennial can grow up to 6' tall. The plant has a single green stem that is 2cm to 5cm thick. The stem is smooth with a few hairs, hollow and grooved. Its leaves are arranged in pairs, with sharply toothed leaflets shaped like a mitten.

The plant flowers from May to late autumn. Its florets are small and yellow. The clusters are umbel shaped (meaning they look like an upside-down umbrella) and measure approximately 10cm to 20cm across. After blooming, the plant begins to die, and many seeds are produced in the umbels. These seeds can remain viable in the soil for four to five years. The seeds are round, flat and winged.

One of the most characteristic features of the plant is its distinctive parsnip-like odor.
 
 
 
 
     
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