- Author: Jenni Dodini
Published on: April 28, 2021
Tyler and I were doing some yard work at his house the other day, and all of a sudden I hear "Gramma, HURRY!!! Come look -- HURRY!" So I go over to the olive tree he was supposed to be trimming the suckers off of and there sat a very pretty insect, clearly, not a grasshopper, but bigger. "HURRY, go get a jar from the house so we can catch it!!!" I did not have the presence of mind to take a picture of it immediately. Once in the Tupperware that he brought out, it turned brown. Of course, I haven't been able to find another pretty one to take a picture of.
Now, the next question is, "What is it?" Really, not a clue. My mind went to some kind of insect that gets into the grapes across the road. Sharpshooter? No, not ugly enough. Better go get the book and computer and start looking. In the meantime, Steve comes in and looks at it, hears the story, and doesn't know what it is either. So we decide that since it was in the olive tree, it must have been there for a meal, and we should let Jacob know. (Jacob is the man who manages the olive trees on our land.) Jacob comes over and "Oh yea, that's a cicada. They are all over back there. Not a problem." OK. The Ag director knows they are here, and has been out to see them already. Again, OK.
Now Tyler decides that he MUST inform his Ag Science teacher that he has caught this bug. I tell him that he may have to make a report, but he wants me to text her anyway. Done. Now for the research part for the report. He lost interest fairly quickly, after looking at pictures on Wikipedia. There are many amazing pictures and we found the one that looked most like the insect we found on the tree. Then off to the real science sites (teaching moment that caused the total loss of interest in doing the research). Nothing found online about cicadas in California. Every site was talking about the coming of the locusts, as cicadas are also known, to the part of the country east of the Mississippi River. They are calling this year's bunch of "periodical cicadas" Brood X. The US Forest Service site shows a map of where they most commonly are found. Very impressive, and again, nothing about California. The Scientific American site also talks about Brood X but expands and includes the past broods as well. Periodical cicadas emerge every 13 to 17 years, but can emerge up to 4 years early depending on climate. It is expected that the global warming that we are experiencing may cause this early emergence to continue. There are two families: Cicadoidea and Tettgarctidae; Order: Hemiptera. The Cicadoidea has more than 3000 identified species and is found all around the world. The Tettgarctidae family has two species found only in Australia.
The life cycle was explained very concisely:
The sun warms the ground where the nymphs have been growing and they emerge from the soil. The sun warms their wings and they swarm into the trees and mate and suck the sap from the branches and lay their eggs. When the eggs hatch, the nymphs fall to the ground, burrow into the soil, and feed on the tree roots. The nymphs grow VERY slowly, taking 13 to 17 years before their development is complete, which is why the trees are not damaged from their feeding. The adults mate and die within one month. The adult females can be up to 2 inches long!
The best information regarding cicadas in California that I found was in our text, "Pests of Landscape Trees and Shrubs", Second Edition, Publication #3359, page 152. It says that there is no known control agent for cicadas besides pruning off the affected branches to prevent the eggs from hatching, "if possible". Cicadas are relatively uncommon in California and they don't cause much plant damage.
Cicadas are the loudest of insects. The males attract the females by producing high-frequency vibrations which humans can also hear from long distances. There are drum-like structures on the abdomen called tymbals, some of which are hollow and act as resonance chambers. Now that I know they are out there, I notice the humming sound every time I go outside.
And yes, I presented Tyler with the research and made him pick out what his teacher would want in the report. And he took the cicada he caught to his teacher.
The brown leaves are damage caused by the cicadas sucking out the sap from the branch.