Beech Tree News Network

When I hear the word “parasites,” it always brings to mind my late father-in-law, J.D. Hughes, sitting at the kitchen table, drinking coffee, smoking cigarettes and denouncing coal mine inspectors.  “Damned government parasites!” he would say about the government employees, who would show up at his mine site unannounced to make sure J.D. was following all the mine safety regulations.  J.D. wasn’t big on other people being “up in his business.”  Anyway, the word “parasites” has always carried with it negative connotations for me.

Being a lover of all-things-Christmas, you can imagine how it grieved me to find out Mistletoe is a parasite.   Well actually, it is a hemiparasitic plant, which means it obtains some nourishment from the host, but also photosynthesizes on its own, making some of its own food.  When trees shed their leaves in the fall, you can see mistletoe growing in bunches high in the trees.  European mistletoe grows on apple trees, poplars, willows and hawthorns.  North American mistletoe, called Eastern or Oak mistletoe grows on deciduous trees, including oaks (britanica.com).

I’m sure you’ve heard how poisonous mistletoe is to the human digestive system.  According to poison.org, there is a difference in toxicity between the European and North American plants, with the European mistletoe being the more toxic of the two.  The poison site says the North American plant is reported to be poison, probably due to guilt by association to its European relative.  Their study found differently.  

“Our study examined the outcomes of 1,754 American mistletoe exposures.  The overwhelming majority of exposures occurred during the Christmas season when American mistletoe is used decoratively.  Children accounted for 92 percent of these cases, and 96 percent of all exposures were by swallowing.  The vast majority of patients had no symptoms, and there were no fatalities, including 72 people who swallowed mistletoe on purpose” (poison.org).  You gotta love those last 72 brave souls.  I’m sure they did that in the name of science.

I discovered another interesting parasite just this fall.  Garey brought in a small papery ball he found on an oak leaf.  When Garey finds a thing he can’t identify, he always brings it too me, because he knows I will search to the ends of the earth till I find out what it is.  I have two of those nature apps on my phone, so I took a picture of the papery ball and waited for a result.  

The papery ball turned out to be a gall, made by the Oak Apple Wasp, another creative little parasite.  “The entire life cycle of an oak apple wasp, spread over two years, happens on one single oak tree” (brandywine.org).  The life cycle begins underground in the roots of the oak tree.  Wasp larvae hatch and feed on oak tree roots.  Larvae becomes pupae, and from pupae to wingless adult females.  In the spring of the second year, the female wasp emerges from the ground and climbs the oak tree to the leaves.  The adult wasp injects an egg into the veins of the new oak leaf, where the gall begins to form.  It is the hatching egg, releasing chemicals and hormones, that causes the small ball to form on the leaf.  The ball becomes home to wasp larvae.  In June or July, the larva becomes a pupa, then an adult wasp, who exits the gall by making a hole.  The gall falls to the ground—where Garey found it and brought it to me.  The males and females mate, the female goes back underground to the oak’s roots, and the cycle begins again (brandywin.org).

According to the research, Oak Apple Wasps don’t hurt humans—they are only about ¼ of an inch long—are beneficial to birds as food, and they don’t hurt oak trees.  Of course, that’s human observation, nobody asked the oak tree.  Mistletoe, on the other hand, can take over a tree, causing the tree to be stunted, or in draught conditions, to die (arborilogical.com).

The word “parasite” comes from Latin parasitus and Greek parasitos and means, “one who eats at the table of another” (Wikipedia.org).  You know what this means.  We have all been parasites at one time or another.