Cicadas “eat” / drink something called xylem (sap), which is a watery tree fluid containing amino acids and minerals. Cicadas drink rather than eat.
People probably ask “what do cicadas eat” because they are afraid that cicadas will eat their flowers and garden fruits and vegetables. Cicadas lack mouthparts that can chew and swallow vegetation. Your tomatoes and marigolds are safe.
How does a cicada drink xylem? The cicada’s mouth parts (aka rostrum or beak) are in the shape of a straw, which can pierce rootlets, roots and branches.
- The labium form the outside of the beak of the cicada; inside the labium is the stylet which is comprised of the mandibles and maxillae, which the cicada uses to pierce plants and drink their sap.
- The labrum connects the labium to the rostrum…
- The rostrum, or what people call the “nose” of the cicada, contains enourmous pumping muscles (1) that suck the xylem up into the cicada.
- The cicadas’s polymerized, viscous saliva plugs up any holes their mouth parts create (2), so a root will not continue to leak xylem when the cicada moves on to a new root. They put the cork back in the wine bottle, so to speak.
Cicadas are able to derive nutrition from the xylem thanks to bacterial endosymbionts that live in the cicada’s gut.
Cicadas are known for drinking xylem from tree roots (as nymphs) and branches & twigs (as adults), however, when they are small they must rely on grasses, and possibly other small plants for nourishment.
- Young cicada nymphs are smaller than a grain of rice when they first begin feeding so the tiny roots of grasses are the best fit for their small beaks.
- Grass roots are likely the first roots a young cicada nymph will encounter, as they are close to the surface.
- Deciduous trees shed their rootlets in winter months, but grasses do not (2). This is not an issue in tropical regions.
Perhaps the reason why periodical cicadas are “attracted to woodland edges and exposed aspects, especially for chorusing and ovipositing” (1) is their offspring will be more likely to find the roots of grasses in those areas. Young nymphs would be unlikely to find suitable tiny roots deep in a shady forest.
Once the cicada nymph is larger, they can burrow to larger and more permanent tree roots, and feed on there.
It is interesting to note that not all cicadas feed on trees. Some feed on sugarcane, which is a giant grass (we’re back to the grasses again). The Brown sugarcane cicada (Cicadetta crucifera) and Yellow sugarcane cicada, (Parnkalla muelleri) of Australia feed on the sugarcane plants and cause damage to plants.
Read more:
Sources:
- 1 The Ecology, Behavior, And Evolution Of Periodical Cicadas, Kathy S. Williams and Chris Simon, Annu.Rev. Entomol. 1995. 40:269-95
- 2 Xylm Feeding by Periodical Cicada Nymphs on Pine and Grass Roots, With Novel Suggestions for Pest Control in Conifer Plantations and Orchards, Monte Lloyd and Joann White, OHIO J. SCI. 87 (3): 50-54, 1987
Hello,
Do you know when they begin to feed after exiting their exuvium? Is there a window of time were it is ok if they are not eating? Last night I held one angled as I see them on trees sometimes as it emerged. I found her on the sidewalk coming out of her exuvium already. I have a branching piece of driftwood that she (has an ovipositor) climbed onto after bending backward from her shell for a time. She looks good her wings seem to be fine and she has climbed on top of a wooden basket I have.
From looking at your pictures I think she might be a N. linnei. Her collar has no break and she has a warmer coloring around her M. Looking at the wing I’m not sure though.
I’ll likely let her out sooner than later today…I just wonder when the best time is? I figure you might not get back to me today so this is also for future reference as this is the second time I have done this. Last one I did wait till night because of storms and gave him water though he did fly a couple times until I put him in some mesh in a dark place.
In any case thank you for all the cicada info!
I had dozens of cicadas on my ostrich fern I photograph them on Friday there were so many it looks like an invasion. Today those Ostrich Ferns are all curled up and turning brown. I can’t imagine it was caused by anything other than these cicadas they look so healthy and fine just a couple days ago.
They are all over the coleus in the garden; the plants are seriously wilted. I guess this plant can be added to their food list? Didn’t know coleus were sap producing. Interesting event!
Can you tell me where to find a list of which shrubs the are vulnerable. I already know which trees. I have about 180 newly planted trees and shrubs, all native to my area if Maryland. I need to know which one I need to cover and which to skip. I am already covering all the trees.
Do I need to cover:
Oak-leaf hydrangea
Ninebark
Viburnum
Gray dogwood
Fothergilla
Beautyberry
Wax myrtle
Bayberry
Inkberry
Winterberry
Chokeberry
Spicebush
Bottlebrush buckeye
Serviceberry
Laurel
Azalea
Rhododendron
Grow-lo sumac
Clethera
Itea
Thank you so much if you can answer this!
@Dawn — I honestly don’t know, which is why I’ve been asking folks to speak to arborists, landscapers, tree experts, etc.
Personal experience: I’ve seen them kill branches on hardwood trees — oaks, maples, dogwoods, etc. I can’t remember if they did any damage to my laurel, azalea, or other let’s say “shrubs” — but I personally didn’t lose a single tree or plant. Your experience might vary, so talk to a landscaping plant expert.
Okay thank you
Can you build a habitat inside for a wondering Cicada. I built a Slug environment and my wonderful slugs are 2 years old. They both burrow but I don’t want it to be a schmorgasbord. We take a great deal of care to make the wonderful visitors comfortable. Can you lead me to more information on habitats for these wonderful visitors. I love every thing that walks crawls or slither through my yard. I hope someone will contact me to maximize the bug accomodations. Slugs are wonderful. cured a 3rd degree oil burn on my hand but going to the slug pods and having a few walk over waxless wax paper with cold water on it. I just use it to but on burns and have avoided having a skin transplant. In just a day and a half it healed. However the moment I put some of their secretion on the burn the pain subsided almost instantly. Judy Goldlbum drlollipop@aol.com
Here’s what I’ve done in the past. I get a small maple tree, like 3′, and put it in a pot. Water it. Enclose it in a small cage made of some kind of netting they can’t get out of.
We cut down a dead oak tree last year. Did the tree dying kill the cicada underground?
Sometimes, but often the cicadas find roots from other trees or use grass roots when there’s no other choice. As long as they didn’t dehydrate, they probably have enough fat to survive.
I live 45 minutes N of DC. We are due the 17 year Cicadas this year. I bought 3 esplaired fruit trees to plant this year. Should I keep them in their pots till the cicadas come and go?
It might not be a bad idea. They’re usually gone the last week of June.
Wrap the base with netting or tulle to keep them from sucking the sap or cutting slits in the base of the trees ( that’s where they lay their eggs).
They will not bite nor sting what they like to do the most is piss on you when they fly away from you they leave you with a squirt if pee..
I was gathering some Swiss Chard from my garden and found two on the back of a chard leaf!
There weren’t any on anothers. If they can drink from grasses can they from Swiss chard?
Ik they eat xylem but how do I give that to my cicada
I don’t know ether, maybe give them maple syrup. Maple syrup is only boiled down sap, maybe that will work?
They like the first layer of sap called xylem, which is thinner and more fluid, like water with some electrolytes and amino acids. The more maple syrupy sap is called phloem.
You can put it on a tree and let it feed, then take it back inside
Appears we are not in the area for the 17 year but I know we have had them in the past. A question I have is people I know own a vineyard and many of their vines have died. They blame it on the 17 yr cicada getting ready to arrive. I disagree. Is it possible that they are killing the vines? Everything I read makes it seem unlikely.
@Beth, seems unlikely, but I wouldn’t rule it out without inspecting the vineyard, roots, and soil. If they planted their vineyard where groves of trees once stood, the cicadas might try to feed on the roots. Could be something else like the Spotted Lanternflies.
Thank you for the explanation of our chicadas. These facts are so interesting 😂
I have always liked them.
I love cicatas
Hi Dan! I live in the town of Lakehead, in Northern California, the north end of Lake Shasta.
We have a year round running creek behind
our house. There are a lot of fir trees, black oak trees,
and redwood trees all around the house. I had found quite a few eckoskeletons down in my rock garden near the creek and have been hearing a loud clicking noise from the trees all around the house. I’m picking up dead ones in the driveway now to show my husband that doesn’t believe they are in the trees!
It sounds like there must be hundreds of them. I hear them but he says he doesn’t! What can I do to protect my redwoods that are around my house? I’m worried about them! Thank you!
@Annie — the clicking cicadas belong to the genus Platypedia. The most common species is called Putnam’s cicada https://www.cicadamania.com/genera/species.php?q=P.+putnami+putnami#soundzone
Sorry about my last post – I meant fruitless bradford pear trees. I have 2 near each other and one looks like it is dying (West Virginia). Could it be the Cicadas?
They might feed of their roots. Most of the damage cicadas do happens when they lay eggs in the tree branches. Unless you had a lot of cicadas in your trees this year (or last), it probably isn’t cicadas that led to the death of your tree.
I live in Washington DC and I Still haven’t seen them Yet. Does this mean we get a pass? Lol
Yes. For better or worse you get a pass.
I’m in southern Utah and we have a large hatch. Will they damage my trees and flowers? The grandkids love playing with them!
the Utah varieties are a lot easier on the trees than the eastern US varieties.
I fond a outbino wun
Do you still have it? I’d like to see a photo of an albino.
Just today noticed cicadas emerging in northeastern TN (Washington county). Presume these are brood 10 stragglers (4 years early) or possibly brood 6 (due 2017 in NC) that are on the “wrong” side of the mountains! Any way of telling which brood they are from?
Yes the might be Brood VI.
I found 12 exoskeletons on two windows in the backyard wow Never seen that many in one area!
I’ve noticed since the cicadas came out some of the other usual pests have not. the gnats have died down, no gypsy catepillars, no pinchers, no millipedes. all the bugs that plague us this time of year. is it because of the cicadas? If so I love them
I find the cicadas cool. Especially when u find their exoskeletons on trunks of trees ,branches,ab under the leaves.but the ones that showed up so far,are so much smaller than in the past. Also while searching for them i noticed that many of them were still in their exoskeleton an didnt make it..
They are everywhere! How impressive!
They are on my flowers and now all are wilted. What can I do to save my flowers?
Try spraying the cicadas off with a hose to remove them. Make sure your plants are watered to regain any fluid loss from the cicadas hanging on them.
Thank you, Dan. Gettysburg PA I have literally about 150 so far.
They are eating my Walking Onions!!! Are they supposed to? I live in Stark County Canton Ohio, they showed up all of a sudden this morning…Help…Thank you Miss Jeri
They’re probably just hanging on the onions and not eating them. They can’t actually chew.
what cicadas eat
They eat by drinking xylem which is a variety of plant sap. Once they drink it bacteria in their gut process it into food for the cicada, like how bacteria help termites digest wood.
Above ground they drink sap from tree branches and live off the fat stored in their bodies.
Hey Dan! You seem like you know a lot about cicadas, I have an injured on I’m hoping to fix. Any advice would be appreciated!
Depends on how it is injured.
Typically when their wings are injured, they’ll never fly, although some can still crawl around and find a mate. It’s easier for males because they can still sing and attract a female to come fly to them.
Injured cicadas can be kept as a pet, so to speak.
You have to cut a tree branch and keep it in some water like a small vase or courage vial, and the cicada will drink from that.