Cicadas appear in east, expected here soon
Periodical Cicadas (PC) emerged May 8 in two East Tennessee counties. PC populations are expected to emerge here this week over a period of six weeks.
Do not confuse these with our annual cicadas, referred to as dog-day cicadas, jar flies, or harvest flies that appear every year from June to August. The annual cicada is larger with black and green body coloration instead of the smaller, all black PC with distinctive red eyes.
While I wrote about them two weeks ago, this article contains additional information.
Each adult lives about three weeks (or more depending on source) and only the male sings. They will reappear in the same areas as 17 years ago. Egg laying will begin two weeks after emergence.
They do not bite or sting. Dogs, cats, birds, hogs, squirrels and poultry love to eat as many as they can catch.
Damage to pencil-size tree branches occur when the females rip the wood to insert their eggs. They prefer birch, redbud, oak, maple, dogwood, crabapple, elm and hackberry. Each female will lay up to 400 eggs in 40 to 50 sites.
The 20+ eggs placed in each twig hatch five to seven weeks later into tiny, grub-like worms which enter the soil where they attach themselves to tree roots with needle-like mouth parts for the next 17 years. They will not remain in nursery blocks since we sell our trees.
Young branches later break in the wind when egg-laying sites occur on opposite sides of a branch at the same point. A year’s plant growth is basically lost. We refer to a limb breaking, hanging with dead foliage as ‘flagging.’
Flagged and noticeably damaged branches should probably be removed as soon as but not before the cicadas leave, possibly around July 1, to allow time for regrowth.
A damaged branch may get laid into again if left, but if removed too early, the female would select another.
The future cicada population can be reduced by burning the damaged branches within three weeks of the egg-laying process. I doubt it will be significant because of all the eggs laid in the woods surrounding nursery.
I might consider it since labor will have the branch in their hand while making the cut just above an outward facing bud; they can pile handfuls to be picked up at end of the day. Disking or mowing the branches would not kill the tiny insects.
We do not recommend spraying because pesticides are ineffective against this pest. They do not eat, or not enough to kill them before they do damage. A few producers thought they killed some years ago, but they were seeing natural deaths beginning to occur three weeks after emergence.
It appeared driving the air blast sprayer around and spraying water did as much good as anything. It did disrupt their egg laying activity and caused them to drop to the ground.
Let me know when the PC arrives at your nursery. I plan to map them.
Cicada-killing wasps will be more abundant during PC outbreaks and can be bothersome to humans as they dig soil chambers in lawns to place a paralyzed cicada for their young larvae to feed upon.
‘ After seeing the price of generic Roundup drop so drastically, Monsanto decided to regain control of the market. They had invented glyphosate, but when the patent ran out, prices dropped from $90 to $15 per gallon. Monsanto either purchased the small companies selling generic or did something to regain control. I’m not sure.
Doug Partin at Valley tells me, ‘Monsanto now controls all of the generic glyphosate in the world. We can only buy it in allotments every two months. It’s higher every time we order it. Monsanto sets the price.’ (The above prices are from memory.)