Field of Science

Weed of the week - pokin' around

The late summer and fall is when people notice that a huge, attractive looking weed has invaded their yard/garden/alley.  You can hardly miss a plant with big green leaves that stands anywhere from 4 to 8 feet tall on a red stem that is 1-2 inches in diameter.  Also notable are quite handsome racemes of dark purple to black, glossy berries.  There are some ornamental varieties of some other species. This is Phytolacca americana, pokeweed or just poke.  Warning: ALL PARTS OF THIS PLANT ARE TOXIC - DO NOT CONSUME, and if you are a sensitive skin type person, avoid the sap.  This plant is a perennial so a mature plant is not killed by cutting off the stem; you must poison the big old white tap root. or dig it out. The young shoots have been gathered and boiled as greens made famous by the song "polk salad (sallet) Annie".  Changes of water are needed to detoxify the greens and its least toxic when young; it scares TPP too much to even try it, And what would be left anyways.  In this case the "salad" stands for sallet in the British/French (?) sense of cooked greens.  Birds and even some small mammals seem able to eat the fruits with no ill effects, so too many seedlings appear under our bald cypress, a favorite perching tree. Best to pull seedlings or chop them off before they get that tap root formed.  
 Here's a flowering inflorescence; the flowers are small with 5 sepals that are persistent.
 This is an older inflorescence showing a sequence of fruit development.  It happens pretty fast.
 This is a nearly mature infructescence showing the round, slightly flattened purple/black berries.  Kids could easily eat any berries this attractive.  Note that the sepals have turned bright pink; thus prolonging their attractiveness even after a berry is removed.
This shows the foliage, a rather simple leaf and the distinctive pink stems.  

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