How To Get Rid Of Pine Sawfly Larvae: Helpful Tips

Pine sawfly larvae can become a big reason to worry for your beautiful pine trees. Let us understand the lifecycle of this pest and how to get rid of pine sawfly larvae.

From the redheaded pine sawfly to the white pine sawfly, enemies are hidden amidst your pine foliage, ready to destroy your plants!

A beautiful symbolic representation of longevity and virtue, pine shrubs are found all across the Northern Hemisphere. These multipurpose conifers are the source of revenue for many businesses.

However, pine sawfly larvae can leave these beautiful shrubs completely naked without their characteristic pine needles, feeding off them in a matter of days. Let’s learn about how to control these bugs.

What Are Pine Sawfly larvae?

The pine sawfly biologically belongs to the Symphyta sub-order of the Hymenoptera order and is part of the same family as ants, wasps, and bees.

Pine Sawfly larvae, as their name suggests, are known to feed on pine shrubs. They can damage the foliage and ultimately cause the death of the shrub.

The female sawflies lay their eggs strategically along the terminal ends of the shrub. Once the eggs hatch, their larvae emerge.

These larvae are of different colors, like black, green, orange, or striped. Most of them have a black head. They can grow up to one inch in size and look very similar to caterpillars in their larvae stage.

When a large group of larvae hatches together, it can destroy the entire needle of the ending branches by eating them away. Over time the shrub defoliates, and it causes a massive blow to the businesses reliant on pine cultivation.

How To Tell Caterpillars Apart From Pine Sawfly Larvae?

Initially, most people don’t recognize these larvae because they look pretty much exactly like caterpillars. However, by the time you might recognize them, they would have already caused a lot of damage, so here’s what you need to watch out for.

The number of prolegs (these are fleshy, false legs on a larvae’s body) in the abdominal region is the main thing that you can use to identify sawfly larvae.

Caterpillars have three to five pairs of abdominal, unjointed prolegs. Sawfly larvae also have them, but they have six or more pairs.

They feed for 4 to 5 weeks before they begin to spin a cocoon to grow into an adult pine sawfly and repeat their life cycle.

What Damage Does the Pine Sawfly Larvae Do?

The hatched larva begins feeding from one end of the pine needle and only moves to the next after the entire needle has been eaten.

The pine needles where the larvae cluster feeds start to defoliate rapidly. They leave behind a dried-up, shriveled, and yellowish-brown section of the branch completely devoid of foliage.

Though many pine shrubs survive the infestation, European pine sawfly Larvae can cause considerable and permanent damage to the conifers. This includes

• Stunted growth
• Non-Uniform growth with areas of permanent defoliation
• Missing aesthetic appeal
• Repeated infestation at the same spot can weaken the branch.

How To Control Them Organically?

Pine sawflies can be taken care of organically in the larval stage by applying these simple methods.

Tolerate Them

White pine sawflies and most other species are harmless to humans and animals alike, as they do not have stingers at any stage of development.

Localized areas of infestations on a specific shrub do not spread or transfer to others. Hence they rarely cause a massive issue; if left alone, they generally fall down to pupate or die. The shrub will grow pine needles back over time.

Therefore, if watching your shrub get defoliated is not too much of a problem, you might consider leaving them alone.

Pluck Them Off

The sawfly larvae are often easy to see. As they hatch and stay in clusters, it is easy to handpick them off. Even though the process is slightly time-consuming, it is the most cost-effective and easy solution.

Beneficial Predators

Parasites, rodents, and birds are beneficial insects that can easily get rid of your sawflies and their larvae. Beetles and parasitic wasps are other natural predators that can help kill sawfly larvae.

In particular, the Bacillus Thuringiensis (BT) is a parasite that is known to be effective against them.

However, it has been noted that they are not an aggressively effective solution and only provide temporary resolution until the next cycle begins.

Prune Branches Infested By Them

Pruning branches is a common practice, especially if the infestation of pine sawfly and the other variants are limited and the Pine conifer is not yet in the harvest stage.

However, pruning can result in causing structural weakening of the conifers, which many do not like.

Pesticidal Control of Pine Sawfly larvae

One of the best solutions for eradicating various species of sawflies is to opt for genetically enhanced variants of pine trees immune to these pests.

However, as that is not an option available to everyone, so most opt for Insecticides when organic routes do not work.

Contact Pesticides

These are the most preferred choice as they do not cause much damage to the environment or the nearby insects. Some of the most commonly used natural Insecticides are

• Pyrethrinrum
• Synthetic Pyrethroids lambda-cyhalothrin
• Deltamethrin
• Cypermethrin
• Flupyradifurone
• Acetamiprid

Though these insecticides are not dangerous, it is best not to spray on the adjacent flower and fruit plants.

They can cause harm to the bees and other pollinating insects and birds. You can also try spraying the Piner conifers with soapy water as a quick, cost-effective, and hassle-free solution.

Horticultural Oil

One of the oldest natural insecticides used by gardening experts for centuries is Neem Oil. The natural oil works on any species of sawfly and larvae.

Neem Oil contains Azadirachtin, which is extracted from Neem Seeds. Other potent oils are meliantriol, fatty acids, and salannin.

The oil acts by attacking the entire life cycle of Pine sawflies in various ways, preventing adult Sawflies from laying eggs and larvae from growing further.

Most importantly, natural oils are not harmful to bees or other beneficial insects. Some of the most commonly available Horticultural Oils are

• Orthene
• Bio-Neem, Margosan-O
• Sevin
• AzaMax

What is the Best Time To Use Pesticides on Pine Sawfly Larvae?

The insecticides are most potent when sprayed on the larvae when they are small. The larvae are at their weakest when they are about half an inch in size.

By the time the pine sawfly larvae grow up to three-fourths of an inch, they develop resistance to these insecticides and hence are not affected anymore.

Generally, you can spray insecticides late in the evening, preferably at dusk, for the best results. Left undisturbed overnight, they force out even the most conspicuously hidden larvae out into the open by the next morning.

Most of them are dead by then, and you can easily handpick and squish the rest. Despite the measures taken, these natural enemies of the Pine conifers reappear every other year at the same location.

This is because these bugs fall off onto the soil when they pupate and stay there until it is time to emerge as adults and lay eggs again.

If the soil is not cultivated and treated regularly, the sawflies are bound to come back.

Frequently Asked Questions

Nothing Beats Constant Vigil!

Keep an eye out for even the smallest changes in the Pine shrubs. The clues are always hidden in plain sight, from black spots to drying sections.

Don’t get fooled by their caterpillar-like appearance, and use the tips we gave here to keep your plants safe. Thank you for reading!

Reader Emails

Pine sawfly larvae can be a real menace to pine and other deciduous trees, and our readers have often discussed their encounters with these bugs in a negative light.

Go through some of the emails from readers to see for yourself the damage these pests can do and what methods they might have adopted to stop them.

Letter 1 – Red Headed Pine Sawfly Larvae

 

destructive worm/caterpillar…moving fast…help! July 26, 2009 Please help me identify this alien army that has shown up and destroyed my evergreen bush in less than three days….will they move on to my other flowers and trees?? Laurie Southeastern Massachusetts (Plymouth County)

Dear Laurie, We identified your Red Headed Pine Sawfly, Neodiprion lecontei, on BugGuide, and now that you know what it is, you should be able to find much information posted online.  You do not need to worry about these larvae that are related to wasps moving to other plants in the garden.

They feed on “Preferred hosts are red, Scots and jack pines. Also attacked are shortleaf, loblolly, slash, pitch, Swiss mountain, Japanese black, mugho pines, white pine, larch, deodar cedar, and Norway spruce” according to the Forest Pests website.  The Forest Pests website also indicates:  “Larvae may defoliate an entire tree from the top downward (b). Young or stressed trees are preferred, and small ornamental pines may be completely defoliated and killed in heavy infestations. Trees that are growing in poor sites or under stress are attacked more readily than healthy trees. Damage can sometimes be reduced by getting rid of competing vegetation, planting in high-quality sites, and promoting early closure by close plantings. If infestations are light, manual removal of larvae may effectively control the pest.”  The Discover Life website also has much valuable information and control suggestions.

Letter 2 – Sawfly Larva: What does more damage? A Sawfly Larva eating Leaves or a Crew Cutting Branches???

 

Found this larva in gunni euc tree need id? February 23, 2010 While cutting gunni euc one of my workers found this worm. I need it id to know if I it is harmful. It is white had has black spots on the side. The face almost looks like it is smiling. Please help!! Jennifer Watsonville ca

Hi Jennifer, This is the larva of a Cimbicid Sawfly, a non-stinging relative of wasps and bees.  The Sawfly larva will eat some leaves, and we believe it is doing far less harm to the plant than the workers who were probably cutting branches.

Letter 3 – Pine Sawfly Larva

 

Subject: Caterpillar ID Location: York Region Forest, Newmarket, Ontario, Canada November 6, 2013 10:36 pm Hello Bugman, I would like to get some info on this caterpillar. It was found in York Region forest, just half hours drive of Toronto, Ontario, Canada. It was searching on old decaying tree trunks in the parking lot when I first spied it, during the middle of October 2013. A few days later, I found a second one (may be same one) in the same location. I took both photos, of which you may use for display purposes. I have been searching many butterfly and moth categories, without any luck in naming it. Maybe (I’m thinking) its a sawfly? Its about 1 1/2 to 2 inches in length. I have just started a website and trying to name the species that I have included on it. Thanks for any info… Brian

Dear Brian, Just because it looks like a caterpillar and acts like a caterpillar, does not necessarily mean it is a caterpillar.  You are correct that this is a Sawfly Larva.  It is an Introduced Pine Sawfly Larva, Diprion similis, and according to BugGuide, it is an adventive species introduced from Europe.  BugGuide also notes:  “Although a serious pest at times, it normally stunts rather than kills its hosts. It can be a more serious problem with young trees and in cases such as Christmas trees where appearance is important. It has natural enemies and diseases, so large outbreaks are only intermittently seen.”

Dear Daniel, Many thanks for your reply -to my request asking for identification, regarding the bug that I had found – most informative. No wonder many of the conifer trees in that area that it was found in, had issues with their foliage etc. Brian

Letter 4 – Sawfly Larvae near Milkweed

 

Subject:  Are these Monarchs? Geographic location of the bug:  gilford, nh Date: 08/30/2017 Time: 02:49 PM EDT Hi, Found this hatch a leaf between leaves in a patch of milkweed. They have the coloring of Monarch caterpillars, but I have never seen so many together. Do you know what they are? How you want your letter signed:  Curious in NH, Wendy O.

Dear Wendy O., These look more like Sawfly Larvae to us.  Sawflies are non-stinging relatives of wasps and bees whose larvae resemble caterpillars.  Here is a BugGuide image of a Sawfly larva in a similar position, and here is a BugGuide image of a similar grouping of Sawfly Larvae.  Finally, here is a BugGuide image of a really similarly colored Sawfly Larva, but alas, it is not identified to the species level.  We are posting your image and perhaps one of our readers will be able to assist with a species identification.  Were they actually on Milkweed? Hi, No, the leaves were intermingled with the milkweed plants which had sprouted up in our flower garden.  Thanks for letting me know. They looked so much like mini monarchs that I was confused.  I’m in the garden and outdoors a lot and had never encountered anything like these.  Thanks for responding so quickly. Best regards, Wendy O.

Letter 5 – Red Headed Pine Sawfly Larvae

 

Subject:  caterpillar cluster Geographic location of the bug:  raleigh, nc Date: 09/04/2017 Time: 12:11 PM EDT what in the world is this? do we leave them, feed them to our chickens, or what? How you want your letter signed:  carrie

Dear Carrie, Though the insects in your image resemble Caterpillars, they are actually Sawfly larvae.  Sawflies are non-stinging relatives of Wasps and Bees that have larvae that frequently resemble Caterpillars.  Thankfully your image quality was of a high enough resolution that we were able to crop more closely to help identify these Red Headed Pine Sawfly Larvae,Neodiprion lecontei. There is an excellent page on Featured Creatures devoted to this species where it states:  “Neodiprion lecontei is an important defoliator of commercially grown pine, as the preferred feeding conditions for sawfly larvae are enhanced in monocultures of shortleaf, loblolly, and slash pine, all of which are commonly cultivated in the southern United States.”  We don’t know if the Red Headed Pine Sawfly larvae are able to retain within their bodies resinous compounds from the pine that might make then unpalatable, but we imagine if they don’t taste good, the chickens won’t want to eat them.

Letter 6 – Introduced Pine Sawfly Larva

 

Subject:  Caterpillar Geographic location of the bug:  NW corner Connecticut Date: 08/19/2019 Time: 07:15 PM EDT Your letter to the bugman:  Looking for an ID. Consulted the Exec Director of Audubon here in CT and he did not know. How you want your letter signed:  Lori Welles

Dear Lori, We thought this was going to be an easy identification, but more than an hour later, we can state unequivocally that we were way wrong.  Our mistake began by not looking at your image that closely, and thinking we were trying to identify one of the Hooded Owlet Caterpillars in the genus Cuculia, but after ponderously searching BugGuide, we realized we were wrong.  Our search next took us to The Moth Photographers Group where the Zebra Caterpillar looks similar, but not the same, and the Scribbled Sallow Moth Caterpillar pictured on The Moth Photographers Group and the Toadflax Brocade Moth Caterpillar, also pictured on The Moth Photographers Group also looked similar but not the same.  The solid black head on your individual and the round yellow lateral spots were quite distinctive and not found on any caterpillars we could locate.  Something about the head did not seem right, so we decided to count prolegs, and there appear to be seven pairs, which caused us to think this must be a Sawfly larva.  According to ThoughtCo: “Caterpillars may have up to five pairs of abdominal prolegs (tiny limbs) but never have more than five pairs. Sawfly larvae will have six or more pairs of abdominal prolegs.”   Once we searched for Sawfly larvae, we came to Wildlife Insight where we found images that match your individual that are identified as Diprion similis.  Armed with that information, we returned to BugGuide and located matching images of the Introduced Pine Sawfly larva, but the individual in your image does not appear to be eating pine.  Upon what plant did you find it?  According to BugGuide:  “hosts: pines (Pinus); 5-needled pines (Subg. Strobus) are preferred, but others may be infested as well.”  This BugGuide image contains the information:  “This one was on a poplar plant, and the other was eating oak leaves.”  Thank you for submitting this challenging identification request. This was feeding on Cosmos. Glad it was a challenge as many friends including the Exec director of Audubon here in CT. could not ID. LBW Welles, The Ballyhack

Letter 7 – Red-Headed Pine Sawfly Larvae

 

Subject:  Strange caterpillar Geographic location of the bug:  Eastern Virginia Date: 06/14/2020 Time: 07:55 PM EDT Your letter to the bugman:  Hello! I spotted a strange caterpillar at Weyanoke Bird and Wildlife Sanctuary in Norfolk,and pointed it out to my father. I got my phone out and snapped a few pictures of it. I guess my phone hit one of the branches and about 3 of them put their head back and exposed their chest that I saw was covered in spikes (They may have been sharp legs, but I couldn’t tell). They stayed like that for a bit until I backed away. I tried to find them on google, and I looked on a few bug Identification websites, but I saw none that looked like it. I was wondering if you knew what it was! How you want your letter signed:  Lydia Simon,age 13

Dear Lydia, Though they look very much like caterpillars, these are actually Red-Headed Pine Sawfly larvae, Neodiprion lecontei.  Here is a BugGuide image for comparison.  Sawflies are non-stinging relatives of bees and wasps.  When larvae are numerous, they may defoliate trees.  According to Featured Creatures:  “After mating, female sawflies lay eggs in slits sawed in pine needles. Small larvae feed on outer needle tissues; larger larvae consume entire needles. Most species prefer older foliage, but all foliage is susceptible at end of growing season. Larval colonies may migrate from one tree to another, especially upon complete defoliation of the host tree or high feeding competition.”

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Elm Sawfly

 

Subject: Mason Wasp? Location: Western Pennsylvania July 21, 2014 12:02 am I found this on a walk through the woods today and after thorough investigation, I couldn’t quite find a match to any other wasp. The blue tinted wings and black/white body pattern lead me to believe it’s a mason wasp(?), although I don’t know enough about bees/wasps/hornets to confirm. It’s hard to tell in the picture, but the legs and antennae were both bright yellow, which I have yet to see on a Google search of any other. Help me identify? Thanks! Signature: c.g.

Dear c.g., This is an Elm Sawfly, Cimbex americana, and though Sawflies are classified in the same order, Hymenoptera, as Wasps, they are not true wasps and they do not sting.  The larvae of the Elm Sawfly are frequently mistaken for Caterpillars.

Letter 2 – Dogwood Sawflies

 

Subject: Caterpillars on a red-twig dogwood Location: Chester County, PA August 12, 2014 10:17 am While working with a client in their garden yesterday, I noted these caterpillars on a Cornus sericea (red twig dogwood) shrub. I have not seen these before, and would like to know what they are. Fortunately, the clients were just as curious, and willing to “live and let live”, especially as there was very little foliage damage. This is in southeastern Pennsylvania, photo taken August 11, 2014. Thank you! Signature: The Gardening Coach

Dear Gardening Coach, Though they are easily mistaken for caterpillars, these are actually the larvae of Dogwood Sawflies, Macremphytus tarsatus, and they are members of the order Hymenoptera that includes wasps, bees and ants.  According to BugGuide:  ” Young larvae are covered with a powdery white waxy coating. Mature larvae are yellow beneath with black spots or cross-stripes above.”

Letter 3 – Willow Sawfly from England

 

Subject: Catapillar identification Location: Rochdale-manchester-England September 27, 2014 6:09 am At home I have at least half a dozen catapillars and am feeding them apple at the moment but I am unsure of the species that the catapillar is;consequent not being able to feed them ther favourite food.if you can reply as soon as that would be fantastic so I can understand what to feed them 🙂 also the catapillar has an orange tail and blue body with a black and orange head ,it also has random black spots speckled over its body Signature: Alex:L

Dear Alex:L, Though it looks like a caterpillar, this is not a caterpillar, but rather a Sawfly Larva.  We believe we may have correctly identified it as a Gooseberry Sawfly Larva, Nematus ribesii, thanks to this image on FlickR.  According to DownGardenServices:  “The caterpillar-like larva is light green with black dots and a shiny, black head. If disturbed it clings to the edge of the leaf while bending into a S-shape. All of the leaves can disappear with only the stalks and a few veins remaining. Check any leaves beyond them and the larvae will be there, so they can be rubbed off.  The lack of foliage weakens the bush and it produces a very poor crop the following year.”  An even closer match is the Willow Sawfly, , which is pictured on PBase and Wikimedia Commons.  

Letter 4 – Sawfly

 

Subject: On our burr oak, in Texas. Location: Arlington, TX March 27, 2015 10:49 pm Hi, My partner asked me to grab a picture of this and see if I could help him identify it. He’s been seeing these on our burr oak, here in North Texas, since the leaves started budding this week. He’s says there are “lots” of them. He seems to think they have been laying eggs, but I haven’t seen what they have been up to to confirm this impression (and, obviously, he’s not really a Bug Guy). For the record, it is late March, and the weather has been warming up here for a couple of weeks. (it’s up to the 70’s and low 80’s this coming week, already.) I have included both the closer detail crop, adjusted for clarity, and the wider shot for some idea of size. They are small, probably… a half-inch? Maybe? Those are very early leaf buds at the end of an almost twig-like branch that this one is sitting on. (Sorry it is not more clear, it was already evening when he asked me to take the photo.) Thanks! I hope you can help us out! Signature: Kelly in Texas

Dear Kelly, We believe this is a Sawfly, a non-stinging relative of wasps and bees.  The theory that it might be laying eggs is valid.  The larvae of Sawflies are often confused for caterpillars, and if they are numerous, they can defoliate some plants.  We are going to continue to research this request and we are also going to try to get an opinion from Eric Eaton.  The Ladybird Johnson Wildflower Center website mentions “oak leafmining sawfly (Profenusa lucifex)” as an insect that feeds on Burr Oak, and though we could not find the species pictured on BugGuide, members of the genus look similar. Eric Eaton confirms Sawfly and provides possible species identification Yes, definitely a sawfly, perhaps Pristiphora chlorea. Do you know how to do an “advanced search” in Bugguide?  That is often how I come up with answers for you.  Don’t get me wrong, I enjoy the challenge of finding you an answer! 🙂 Eric

Letter 5 – Large Rose Sawflies from Italy

 

Subject: Orange Abdomen – Plant eggs in stems? Location: Mira, Venice, Italy May 17, 2015 12:26 am Hi dear Bugman, On these roses these insects, I counted 4, proceeds undisturbed to crack the stems, leaving behind a kind of scar. I could go as fat as touching them. The have this very bright orange abdomen and very dark rest of the body and wings. The length is about 1-1.2cm. Apparently the upload does not work. I posted two pics: https://www.flickr.com/photos/maurillio/17557563078/in/dateposted-public/ https://www.flickr.com/photos/maurillio/17122998534/in/dateposted-public/ I’m really curios about this. Glad to find a service like this online. Hope it works 🙂 Thanks, Mauro. Signature: Lord of the manor

Dear Mauro, Lord of the Manor, These are Sawflies, nonstinging relatives of Bees and Wasps whose larvae feed on plants, sometimes eating the leaves, and sometimes feeding on other portions of the host species.  We quickly identified your Sawflies as Large Rose Sawflies, Arge pagana, on the Dutch site tuin-thijs.com where it states:  “The Large Rose Sawfly saws a hole in a Rose (plant) and lays eggs.  The larvae eat the rose. But usually there is not much damage,  because the larva has many natural enemies.”  On Nature Spot it states:  ” Like all sawflies, female Large Rose Sawflies are in possession of a little saw. With it they make parallel cuts in the fresh shoots of the host plant. In the cut a bunch of eggs is deposited. The larvae hatch quite quickly and move in a group to the freshly emerged leaves. The young larvae (yellow with black spots) stay together for quite some time, capable of eating the entire shoot. Older larvae lead a more single life and eat from older leaves as well.”   We also located an Italian site, Agraria.org that might have helpful information for you.  WOW! Thanks Daniel for the quick and comprehensive answer! I took pictures of the larvae last year without knowing they were Sawflies. Thanks also for the great service you are providing! Mauro.

Letter 6 – Bug of the Month June 2015: Elm Sawfly

 

Subject: Giant insect in Seattle Location: Seattle, Wa May 31, 2015 12:03 am I saw this giant insect on an Italian plum in late May in Seattle. It was a warm 75 degree day. It moved slowly on the branches and the butt was pulsating. I made direct eye contact with her. She looked me right in my eyes. Signature: Bugged out

Dear Bugged out, Though it is in the same insect order as wasps and bees, this Elm Sawfly, Cimbex americana, is perfectly harmless to humans as it is incapable of stinging.  A day earlier, we received another identification request for a “Bee with yellow tipped antennae” and we suspected it too was an Elm Sawfly.  Your images are of a living specimen and the other is dead, and we much prefer images of living insects to those of dead insects, so we decided to feature your submission as the Bug of the Month for June 2015.  The Elm Sawfly, according to BugGuide:  “hosts include elm (Ulmus), maple (Acer), birch (Betula), willow (Salix), and basswood (Tilia); adults girdle bark on twigs.”

Thanks for the info and for featuring the sawfly! The insect will live out her natural life as we choose not to kill anyone. Thank you again! Joe Mirabella

Letter 7 – Elm Sawfly

 

Subject: Bee with yellow tipped antenna Location: Fairbanks, AK May 30, 2015 6:30 pm I found this unfamiliar bug on my deck. I’ve never seen one before . It’s larger than the usual yellow jacket. Signature: Sarah

Dear Sarah, Though this Elm Sawfly, Cimbex americana, is related to bees and wasps by being classified in the same order, the Elm Sawfly is incapable of stinging.  We received two recent identification requests for Elm Sawflies, and because the other submission included images of the living insect, we featured that posting as our Bug of the Month for June 2015 though it appears it was also selected as the Bug of the Month for April 2013.  Your submission is nonetheless quite important as we get very few submissions from Alaska.

Thank you! I saw a second one today in a driveway a half mile away. Sounds as if I should give a heads up to the entomologists at Univ. of Alaska, Fairbanks. You give me a starting place. Thanks again.

Letter 8 – Birch Sawfly from the UK

 

Subject: Large winged insect. Location: UK. North west England. PR5 0JY. July 3, 2015 5:12 am Hello. Could you please identify the insect from my garden? It’s wing span was approx.. 50 mm. and it’s body length approx… 40 mm. As can be seen on the photos, it had a single ovoid cream coloured mark on it’s back. It appeared to be in distress. Many thanks. Barry Lewis. it’s wing Signature: Barry Lewis

Dear Barry, Because of it resemblance to North American species, we quickly recognized your insect as a Sawfly in the family Cimbicidae, a non-stinging relative of bees and wasps.  The North American Elm Sawfly was our Bug of the Month for June.  We quickly identified your Sawfly as a Birch Sawfly, Cimbex femoratus, thanks to NatureSpot which states:  “The solitary larvae feed on Silver Birch leaves between June and September and can grow up to 45mm in length. A black edged bluish stripe runs along the middle of the larva’s back for the length of its body. There is a single row of black dots along the side of the body.”  The site also states:  “Local throughout Britain, not very common” and “Uncommon in Leicestershire and Rutland.”

Letter 9 – Elm Sawfly

 

Subject: what is this big insect? Location: Comox VAlley, Vancouver Island July 29, 2015 11:31 pm Dear bugman, this insect came buzzed by us this evening, July 29, 2015. It is the biggest I have seen yet in Southern Coastal BC. We live on the East Coast of Vancouver Island, in the Comox Valley. Our house is by a creek in a semi-forested, green belt area which gives us great opportunity for observation of our flora and fauna. This insect flew by slowly, at first I thought it was a juvenile hummingbird or huge moth. It made no sound other than with its wings when it was flying and did not move very fast. In fact it was still most of the time. I took many pictures, most of them not very sharp. I picked the best ones and hope you can help me figure out what it is that was visiting us. Is it a cicada? a cicada eater? It has stripes on its abdomen, like a wasp. It has those short club-like antennae that remind me of a fly. It has a very small head relative to its body, and is antennae and the outer portions of its legs are yellow. Signature: Monika on Morrison Creek

Dear Monika, This Elm Sawfly is a non-stinging member of the insect order that includes Wasps and Bees.  The larvae of the Elm Sawfly are frequently confused for caterpillars.

Letter 10 – Bottlebrush Sawfly from Australia

 

Subject: Wasp type Location: Melbourne, Victoria, Australia January 29, 2016 8:40 pm Hi. Found a new wasp sp. in my backyard. Looks somewhat like a Popper Wasp, back lacks yellow legs etc. Any thoughts? Signature: Tim D

Dear Tim, This is a Bottlebrush Sawfly, Pterygophorus cinctus, and we previously misidentified as possibly a Potter Wasp ourselves once.  Your image is quite beautiful. Thanks Daniel! I’ve been having a bit of a influx of fly/wasp type sp. into my inner suburban Melbourne (Aust) backyard this summer, including Banded Beefly, Wasp-mimic Hoverfly, as well as other more common hoverfly and butterflies such as Common Darts. Very unusual but very fascinating! Cheers, Tim

Letter 11 – Sawfly

 

Subject: Need help with ID Location: Flower Mound, TX April 9, 2016 8:01 pm I saw this today on my back patio. I tried searching the internet, but I can’t find anything to definitively identify. Its behavior was odd … pincers opening and closing, legs moving in and out, abdomen raising and lowering. It also ended up on its back shortly after the pics were taken still performing the sane actions. Signature: Kari

Dear Kari, This is an Elm Sawfly, Cimbex americana, a non-stinging relative of bees and wasps.  There is some variability in the coloration, but this BugGuide image is a good color match to your individual.  We don’t know what caused the unusual behavior that occurred just before death, perhaps it was just the death throes. 

Letter 12 – Elm Sawfly

 

Subject: scary, shiny black insect with yellow antennae Location: Fayette County, Illinois April 25, 2016 11:47 am I came across this scary looking, very shiny dark blue/black insect with yellow legs and antennae while mushroom hunting in April. I had my camera ready and he was very cooperative, although afterwards I realized I probably shouldn’t have been so close. I have tried to google his description but I can’t find anything that looks exactly like him. I’m very curious. Any help would be appreciated! Signature: Jilla Young

Dear Jilla, This is an Elm Sawfly, and it appears to be on an elm twig.  The Elm Sawfly, Cimbex americana, is the largest North American Sawfly.  Though it is related to stinging bees and wasps, it is incapable of stinging, so though it appears formidable, it is actually quite harmless.

Letter 13 – Birch Sawfly from the UK

 

Subject: Black and yellow Location: East Sussex, UK May 1, 2016 3:35 pm Spotted in my garden on April 30th…unfortunately dead. The lighter patch on the body is in fact bright yellow but the photo is not that well lit. Signature: Sue W

Dear Sue, Your Sawfly reminds us so much of the North American Elm Sawfly that we searched for members of the genus in the UK.  We quickly found the Birch Sawfly, Cimbex femoratus, on NatureSpot where it is described as “Up to 25mm long, the largest British Sawfly. The adult is easily recognised by the pale band on its shiny black abdomen. Wings are smoky brown colour with dark brown margins. The antennae are yellow tipped.”  The site also states:  “Local throughout Britain, not very common” and “Uncommon in Leicestershire and Rutland.”  There is a very nice image on Wild About Britain.  Sawflies are solitary, non-stinging relatives of Ants, Bees and Wasps. Thank you very much Daniel. Greatly appreciate your swift response. All the best Sue

Letter 14 – Unknown Larva probably Longtailed Sawfly Larva

 

Subject: unknown insect Location: Bay Area, California June 14, 2016 2:45 pm Hello, Love this site and use it often! I got this photo from a co-worker and couldn’t identify it with my books or your posts. It was found on a backpack in early June. Is it some kind of horntail larvae? I think you are out in the field, I look forward to your answer when you return. Thanks for your time! Signature: Jess Resource Analyst  | Stewardship East Bay Regional Park District Oakland, CA

Dear Jess, Thanks for your patience, though we received so much mail while we were away that we will never be able to respond to everything.  This looks nothing like the drawing of a Horntail larva pictured on Bug Eric.  It appears to have an ovipositor, and we are not aware of any larvae that possess an ovipositor.  Like you, we are stumped.  We will write to Eric Eaton to see if he can provide an identification.  For now, we will classify it as a Beetle Grub, but we are not convinced that this the appropriate classification. Eric Eaton responds Reminds me of a rat-tailed maggot, except those don’t have legs, which this one clearly does, plus a head capsule….I’m stumped, too. Eric Update:  As we await additional information from Jess, we are featuring this posting and requesting assistance from our readership. Dear Jess, please provide us with any additional information, like size.  Also, was this discovery made on a backpack in the field, or was it shortly after an excursion? Hello Daniel, Thanks so much for your time on this! My co-worker is off at a conference, and didn’t provide a size. However, using his photograph of the backpack(see the blurry strap?);  it looks to be about 2.5-3 stitches long. I measured the reinforced stitches on my backpack and got approx. 8-10mm. When I first saw it and said it looked like a cricket larva, he said it was “a small cricket-size”. After review of cricket larva (no ovipositor) and rat-tailed maggots, I emailed. Maybe a female after a molt? But no wings…. He was out in the field, likely a grassland in one of our parks: Alameda or Contra Costa Counties of the East Bay. Thanks to Eric for his time too. I hope this helps, Jess Thanks for the information Jess, Now that this request is back in our consciousness, we had a thought.  It reminds us of a Sawfly Larva, especially some Australian Sawflies, and sure enough, we found a Longtailed Sawfly in our archives that looks nearly exactly like your image.  Here is another image from the Australian Museum.  Now our mission is to see if any North American Sawflies have the long tail or if this might perhaps be an Australian introduction, a direction in which we are leaning as there are so many eucalyptus trees and other Australian fauna already naturalized in Southern California.  Now, going back to your original request, you suggested a Horntail Larva, and interestingly, Horntails and Sawflies are classified together as Symphyta which you may verify on BugGuide.

Letter 15 – Elm Sawfly

 

Subject: Vermont fly Location: Vermont July 25, 2016 7:29 pm Hey. My buddy was doing work in VT today andd saw this fly on the tower he’s working on. He is curious what it is. Thank you. Signature: Dan H

Dear Dan, This Elm Sawfly is actually a non-stinging relative of Bees and Wasps, and not a true fly. Thank you for your quick reply. You nailed the identification. Thank you so much and keep up the great work!

Letter 16 – Is is Art? or is it a Bug??? Sculptural Elm Sawfly

 

Subject: Unknown bug Location: Huntsville, Ontario. August 8, 2016 7:08 pm Could not identify this one. Wasp? Thanks for any help you can offer. No hurry. Signature: Barry

Dear Barry, When we opened the first of your images, we were so disoriented, we thought we were looking at an insect inspired sculpture, and not a real insect.  It wasn’t until we opened a second attached image that we realized we were looking at a dead Sawfly that had been posed, upended, with its legs functioning as the foundation of the “sculpture” and our orientation returned.  Your insect is an Elm Sawfly, Cimbex americana, and you can compare your dead individual to this image of a living specimen on BugGuide.  Sawflies are non-stinging relatives of wasps and bees, and Sawfly larvae are frequently confused for caterpillars.

Letter 17 – European Spruce Sawfly, we believe

 

Subject: Larva ID Location: Chimney Tops Capstone October 13, 2016 1:35 pm Hello there! Today I was wondering if I could have and ID conformation given to a larva. This larva has been posted to BugGuide (it is my image) and we are currently undecided on an ID. At first I thought it could be a caterpillar, but I am more convinced that it is Gilpinia hercyniae. The thing is, we are not sure about the range of this sawfly larva. It seems to be that G. hercyniae is an uncommon insect, and i have yet to find records of it in TN. Just wanted to see what you guys thought about it. Thanks for your time! Link to the BG page http://bugguide.net/node/view/1297521 It was found on 8/24/16 in the Great Smoky Mountains National Park at the Chimney Tops Capstone , in Sevier County, Tennessee. ~35° 37.725’N 83° 28.682’W ~4,700 feet above sea level Signature: Cicada Lover

Dear Cicada Lover, We agree with you that this appears like it might be a European Spruce Sawfly larva as pictured on BugGuide.  Have you any other images?  It would be great if you had an image where we are able to count the prolegs.  According to Natural Resources Canada:  “Native to Europe, the European spruce sawfly was first reported in Canada in 1922 and in the United States in 1929, but did not really attract the attention of foresters until 1930, when it caused severe damage to spruce stands in Quebec’s Gaspé peninsula. The infestation spread rapidly throughout northeastern North America. The discovery of this infestation led to the development of a national forest insect inventory network consisting of the states in the northeastern U.S.   Sawfly populations began to decline in 1938 with the emergence of a viral disease that affects the larvae, returning to endemic levels in 1945, where it has since remained throughout Canada. Its current Canadian range extends from the Atlantic provinces to Manitoba.”  Tennessee is further south than any reported BugGuide sightings.  Please let us know if you learn anything new from the BugGuide posting.

Letter 18 – Introduced Pine Sawfly

 

Subject: Name that bug! Location: Vancouver WA January 12, 2017 9:23 pm This moth (?) evidently came in on the firewood. What kind of bug is this ? I could not find an image on the internet but I don’t know what search words to use. Signature: Kurious Jo

Dear Kurious Jo, Based on this BugGuide image, we feel quite confident this is a male Introduced Pine Sawfly, Diprion similis.  According to BugGuide:  “adventive from Europe; ne. US (ME-MN to NC-TN) + WA; in Canada, NF-MB & BC.”  We first reported the larvae in Washington in 2008.

Letter 19 – Bottlebrush Sawfly from Australia

 

Subject: I’m having trouble identifying what I believe is a species of wasp. Location: Bayside area, Melbourne Australia. February 2, 2017 6:13 pm G’day BUGMAN!! I’ve got another conundrum for you when you get some spare time. I saw this bug at Mum’s the other day, he was just chilling out on a blade of grass so I took some pictures. He’s a little bit cute, but also looks a bit waspish. From the pages I’ve looked up to identify Australian wasp species I’m having trouble finding an accurate identity for him. The closest I’ve come across is a Potter Wasp, but from pictures they aren’t similar enough. As you can see my little wasp friend has an all black face & eyes & no tiny stick waist. Potter wasps appear to have a much thinner, or longer thin section of their abdomen. Also they have more orange on their face & antenne than my little friend. Would you know of any sites in Australia that allowing uploading of pictures to ask about bug identification like you do? Your website is so much fun to browse around. Thank you again for your time. Have a wonderful day! Signature: Kindest regards, manda.

Hello again Manda, Since the internet is global, whyever would you want to locate an Australian counterpart to our site?  That said, we know of no Australian counterpart to our site, though we do have a sister site in Brazil called Insetologia.  Our editorial staff (as if we don’t have enough to do) has toyed with the idea of applying for grant funding to venture into Australia.  We tend to field many more questions from Australia and South Africa from December through February when much of the northern hemisphere is in the depths of winter, which is the main reason we created a WTB Down Under? tag many years ago, and with 880 unique posts (with yours being 881), it is our most popular tag, followed distantly by Bug Love.  Though its coloration resembles that of a Potter Wasp, its antennae are quite distinctive.  Your non-stinging Hymenopteran is a Bottlebrush Sawfly, Pterygophorus cinctus, and according to Jungle Dragon:  “Sawfly is the common name for insects belonging to suborder Symphyta of the order Hymenoptera. Sawflies do not possess the distinctive thin waist of the other hymenopterans, nor do they possess a sting. Their name comes from the female’s saw-like egg-laying tube, which she uses to make a slit in a plant leaf or stem, into which she lays her eggs. The adult Bottlebrush Sawfly has an orange and black banded body, with a wingspan of about 2cm. Males have feathery (pectinate) antennae.”  The lack of feathery antennae indicates your individual is a female.

Letter 20 – Bottlebrush Sawfly

 

Subject: Bottlebrush Sawfly? Location: Pakenham Victoria Australia February 16, 2017 8:08 pm Hi, just wanting confirmation that this is indeed a Bottlebrush Sawfly. Found it sunning on the edge of a Rose, possibly having a feed of the petal? This is sited in Suburban Pakenham, just out of Melbourne, Australia on a mild Summers day, February 17th 2017. Signature: Brian C

Dear Brian C, This is indeed a Bottlebrush Sawfly, Pterygophorus cinctus, and since males, one of which is pictured on FlickR, have feathered or pectinate antennae, your individual is a female.

Letter 21 – Webspinning or Leafrolling Sawfly

 

Subject: Wasp? Location: Rockmart, Ga. March 9, 2017 3:30 am Can’t figure out what this is??? Signature: Mary

Dear Mary, We believe we have correctly identified your Webspinning or Leafrolling Sawfly as Acantholyda maculiventris or a closely related species based on this BugGuide image.  BugGuide has reports from Mississippi and North Carolina, so your location seems to be within the range of the species.  The species is also pictured on the Farmapest site, though we do not understand what has been written about it.  You need to scroll down to page to view the image.  Sawflies are non-stinging relatives of bees and wasps.

Thank you guys soooo……. much???

Letter 22 – Elm Sawfly from Canada

 

Subject: Curious as to what this creature is Location: Brandon, Manitoba, Canada June 3, 2017 8:06 pm Hello, I was recently at a friend’s place when this creepy fellow was spotted on the ground… managed to snap a picture of it before it noticed me and flew at my face then away. Any help being able to identify this mysterious work of art would be greatly appreciated… it looks like something out of a night mare. Signature: Robert Boretz

Dear Robert, This is an Elm Sawfly, Cimbex americana, a non-stinging relative of bees and wasps.  Here is a BugGuide image for comparison.  According to BugGuide:  “not considered a forestry problem, but [larvae] can defoliate shade/ornamental elms and willows.”  Elm Sawfly larvae are frequently confused with Caterpillars.

Letter 23 – Elm Sawfly rescued from Pool in Canada

 

Subject: Giant flying monster Location: Alberta, canada June 29, 2017 8:41 pm I rescued this from my kids pool, left it in the sunshine to dry out. My bug go to people have no idea. We live in northern alberta, Canada by the Athabasca river. Signature: Susie Jack

Dear Susie Jack, This impressive creature is an Elm Sawfly, a non-stinging relative of Bees and Wasps.  Larvae of the Elm Sawfly look like caterpillars and they feed on leaves, and according to BugGuide:  “hosts include elm (Ulmus), maple (Acer), birch (Betula), willow (Salix), and basswood (Tilia).”  Because of your rescue efforts, we are tagging your submission with the Bug Humanitarian Award.

Letter 24 – Elm Sawfly from Canada

 

Subject: Wasp or hornet Location: Cold lake,Alberta Canada July 7, 2017 9:36 pm Found this massive guy in our pool! Not sure if it’s wasp or hornet. Signature: Emma

Dear Emma, This is neither a Wasp nor a Hornet.  This is an Elm Sawfly, and though it does not sting, it is nonetheless classified with Wasps and Bees in the insect order Hymenoptera.

Letter 25 – Sawfly

 

Subject: What am I? Location: Northern maine June 30, 2017 4:21 pm I have groups of these guys in my potato plants this summer. Not sure what they are, if they sting, if they bite or if they are eating my plants. Please help if you can. Signature: DAMMhstead

Dear DAMMhstead, We believe we have correctly identified this Sawfly as Trichiosoma triangulum thanks to this BugGuide image.  According to BugGuide:  “Larvae feed on leaves of alders (Alnus), ash (Fraxinus), poplars (Populus), willows (Salix), cherries (Prunus)”  so we can’t explain why they are interested in your potato plants.  Sawflies do NOT sting, but they are classified in the insect order Hymenoptera that includes wasps and bees.

Letter 26 – Elm Sawfly

 

Subject: Huge flying wasp/hornet Location: Québec July 17, 2017 1:21 pm Hey guys I saw this huge thing in a swampy area in the woods of western Canada (Québec ) I wanted to know what species it could be? Thanks guys. Signature: Emil

Dear Emil, The Elm Sawfly is a non-stinging relative of wasps and hornets.

Letter 27 – Bottlebrush Sawfly from Australia

 

Subject:  What’s this wasp Geographic location of the bug:  Melbourne Date: 01/20/2018 Time: 05:49 PM EDT Your letter to the bugman:  Wondering what this is How you want your letter signed:  LB

Dear LB, While this Bottlebrush Sawfly is classified in the same insect order, Hymenoptera, as the wasps and bees, it is not considered either.  Unlike wasps and bees, Sawflies, including this Bottlebrush Sawfly, do not sting.

Letter 28 – Sawfly from Slovakia

 

Subject:  What’s this? Geographic location of the bug:  Slovakia, central Europe, mixed oak-pine woods Date: 05/19/2018 Time: 11:05 AM EDT Your letter to the bugman:  I found this bee while hiking through the woods picking up mushrooms (I assume it’s a kind of a carpenter bee, something from Xylocopinae) but I can’t seem to find one that looks like it on the internet. It’s May currently, pretty warm outside already (20°C), but I’m not sure how long has the specimen been lying on the ground (I found it dead already). Also, I should mention, it has tentacles with orange endings wider than the rest of the tentacle.  There’s no section that would visibly divide between the abdomen and chest area. Also, the bee has really long hind legs with slight yellowish colouring at the end of them. It’s almost 3cm long. Has see-through wings about the same length as the bee itself. Has visible mandibulae and maxilae. How you want your letter signed:  T.

Dear T, This is not a Bee.  It is a Sawfly, a non-stinging relative of Bees and Wasps.  It might be a Birch Sawfly, Cimbex femoratus, which is pictured on iNaturalist.

Letter 29 – Elm Sawfly

 

Subject:  Enormous hover fly? Geographic location of the bug:  Isabella, MN Date: 05/25/2018 Time: 11:26 AM EDT Your letter to the bugman:  Hi! We saw this guy on our cabin screen in Isabella, MN (far northwestern corner of the state) on May 24th. He’s about an inch long from head to tail! We’re curious about what he is. Thanks! How you want your letter signed:  Krista

Dear Krista, This is not a Hover Fly.  It is an Elm Sawfly.  Unlike Hover Flies which are True Flies with a single pair of wings, Sawflies are non-stinging relatives of Wasps and Bees that have two pairs of wings. Awesome! Thank you so much! I figured it was much too big to be a hover fly! Krista

Letter 30 – Large Rose Sawfly from the UK

 

Subject:  What is this Geographic location of the bug:  Handworth middlesex Date: 06/27/2018 Time: 07:52 PM EDT Your letter to the bugman:  Can you identify this it was on my rose not seen one before How you want your letter signed:  Wayne

Dear Wayne, This is a Large Rose Sawfly, Arge pagana.  Sawflies are non-stinging relatives of Bees and Wasps that have larvae that are frequently confused for caterpillars.  According to Garden Safari:  “The Large Rose Sawfly is a quite beautiful and shiny animal. The animal is entirely black, except for the abdomen which is yellowish orange. Because of the dark, blackish wings, which are kept over the abdomen, the orange colour may not always be clearly visible. The legs are usually entirely black as well. The animals are not capable flyers, slowly flying about with the legs hanging down. In flight they are quite similar to to some flies, such as the St Mark’s Flies, appearing in spring as well. Males can be told apart from the females by looking at the antennae. Males have wire-like antennes, which are the same size just about everywhere. Females have antennae which get slighter thicker going upwards. The Large Rose Sawfly is on the wing in spring and early summer mainly. Depending on the temperatures most are seen from March to June. Like all Sawflies female Large Rose Sawflies are in possession of a little saw. With it they make rectangular cuts in the fresh shoots of the host plant. In the cut a bunch of eggs is being deposited. The larvae hatch quite quickly and move in a group to the freshly emerged leaves. Young larvae stay together for quite some time, capable of eating the entire shoot. Older larvae lead a more single life and eat from older leaves as well. The larvae are very similar to caterpillars and green with black dots and points. When they feel threatened they assume the so-called S-position. This can be seen in many other sawfly larvae as well. To pupate a firm whitish cocoon is spun near or in the soil. The cocoon actually has two covers. The inner one is smooth and firm. The outer cover has the design of a net. It is the pupa overwintering. The larvae are found on wild and cultivated roses. ”  According to iNaturalist:  “The larvae are gregarious and live in colonies feeding on rose leaves.” Very interesting! How much damage can they do and all so I found a mint Beatle that was nice to look at and thank you for your answer kind regards Wayne Hi again Wayne, We have no personal experience with the Large Rose Sawfly, but from what we have read, the damage is done by the female laying eggs and by the larvae eating leaves.  A large infestation might defoliate a rose bush, but leaves will grow back.  A healthy rose bush should have no problem surviving a small infestation.

Letter 31 – Elm Sawfly

 

Subject:  Identification assistance sought Geographic location of the bug:  My Ashland, OR ~6000 ft above sea level Date: 06/27/2018 Time: 03:06 AM EDT Your letter to the bugman:  I am guessing it’s a mitis fly but I couldn’t find one that looks exactly like it How you want your letter signed:  Susan

Dear Susan, This is an Elm Sawfly, a non-stinging relative of Wasps and Bees.

Letter 32 – Sawfly Larva, NOT Carpenter Worm

 

Subject:  Caterpillar ID Geographic location of the bug:  North Georgia, USA Date: 08/11/2018 Time: 12:01 PM EDT Your letter to the bugman:  Please help ID this caterpillar. I know it’s not monarch. It is boring into wood. How you want your letter signed:  Dave Paulison

Dear Dave, We are feeling very confident this is a Carpenter Moth Caterpillar in the family Cossidae because of its resemblance to this South African relative, tentatively identified as Macrocassus toluminus, though there are no matching images posted to BugGuide where it states:  “Larvae are wood-boring.”  But for the color, it also looks very much like both this posting from our archives and a this posting in our archives which we now believe are also Carpenter Moth larvae in the family Cossidae, but we are uncertain of the species.  Breeding Butterflies has an interesting article on the European Goat Moth, Cossus cossus, another species in the family, and the site states:  “The larvae of this moth do not feed on the leaves of the host plant – instead they bore tunnels though the wood, and live internally inside their host trees. Because of this habit, they are considered a harmful species; most caterpillars defoliate plants by consuming all their leaves. While definitely not beneficial for the health of the host plant, most plants and trees are able to recover from being defoliated. Burrowing directly through the trunks of trees is another story however, and is generally not the type of damage that trees can recover from. Because of this, a few larvae have the potential to kill even larger trees. And because their host plants include trees of economic value such as apple, cherry, walnut or olive, most farmers do not consider them welcome guests.”  We hope we can eventually provide a species identification for all three of our postings that all originate from Georgia and Florida.

Correction:  Sawfly Larva Thanks to Cesar Crash from Insetologia in a comment with a link to Oregon State University, we concur that this appears to be a Dogwood Sawfly Larva, Macremphytus lovetii.  The site states:  “The larvae leave the dogwood to pupate and will burrow into soft wood, and possibly soil, so house siding near a plant may be pitted with pupating chambers. Further damage may occur to structures from woodpeckers seeking to feed on the overwintering insects.”  Though BugGuide does not report the species from Georgia, it is reported from many eastern states, including North Carolina.

Letter 33 – Elm Sawfly

 

Subject:  A bee like bug I can’t identify Geographic location of the bug:  Washington state Date: 10/16/2018 Time: 07:22 PM EDT Your letter to the bugman:  I am a 5th grade science teacher who has her students collect and identify bugs as part of our insect unit.  This is the second time in three years this insect has shown up and I have not been able to figure out what it is with any of the North American guides we use. (Audubon Society, National Wildlife Federation, and others specifically dealing with the Pacific Northwest).  The bug pictured is about 1 inch long with a wingspan of 2 inches.  I hope you can help me identify it.  Not knowing is driving me crazy! How you want your letter signed:  Rebecca Swier, Ebenezer Christian School

Dear Rebecca, Perhaps if this individual had a head, identification might have been easier for you.  This is an Elm Sawfly, Cimbex americana, and here is a BugGuide image for reference.  Sawflies are non-stinging members of the order Hymenoptera, a group that includes wasps and bees.  They have larvae that look like caterpillars. 

Letter 34 – Elm Sawfly

 

Subject:  Any ideas Geographic location of the bug:  Western Washington Date: 05/07/2019 Time: 07:49 AM EDT Your letter to the bugman:  This bug was located by my daughter at her grandparents. I’ve never seen it and neither have they and they’ve lived there for 18 plus years. We became very curious to what it may be but can’t find it through our research. How you want your letter signed:  Curious Father

Dear Curious Father, This is an Elm Sawfly, a non-stinging member of the Order Hymenoptera, a group that includes Bees and Wasps.  According to the University of Wisconsin-Madison Master Gardener Program:  “The adults of sawflies tend to be inconspicuous, and look somewhat like wasps, but do not sting. They feed on pollen and nectar, so may be seen on flowers as well as their larval host plants. They are not very active, making only short flights in sunny weather, and resting on leaves otherwise. Many sawfly species are parthenogenetic; since they do not need to mate to reproduce, males are very rare even in species where males are known to occur.” Thank you so much for the reply. My daughter will be excited to learn what she found. You rock.

Letter 35 – Tree Cattle

 

Subject:  Striped group Geographic location of the bug:  Southeast Indiana Date: 07/12/2019 Time: 03:39 PM EDT Your letter to the bugman:  These are moving in a group on a maple tree. horizontal stripes with no wings. Curious as to what they are. How you want your letter signed:  Kanita

Dear Kanita, These are benign Barklice, commonly called Tree Cattle.    

Letter 36 – Sawfly

 

Subject:  mystery hoverfly Geographic location of the bug:  Mt St Helens, Washington, USA Date: 07/11/2019 Time: 08:08 PM EDT Your letter to the bugman:  Seen June 30, 2019. It’s with body was slightly over an inch (2.5-3 cm) long. Seen at Coldwater Lake, Mt St Helens National Volcanic Monument. A friend thought it might be a species of Tachinid Fly. I would be interested to know if anyone recognizes it. How you want your letter signed:  Linda Severson

Dear Linda, This is not a Hover Fly nor any other True Fly.  Flies have a single pair of wings and your insect has two pairs of wings.  The clubbed antennae characterizes it as a Sawfly, a non-stinging relative of stinging Bees and Wasps.  We believe we have identified it as Trichiosoma triangulum thanks to images on BugGuide.  According to BugGuide:  “Larvae feed on leaves of alders (Alnus), ash (Fraxinus), poplars (Populus), willows (Salix), cherries (Prunus).”

Letter 37 – Honeysuckle Sawfly

 

Subject:  Is this a bee? Geographic location of the bug:  CH43 9AJ Date: 07/13/2019 Time: 03:28 PM EDT Your letter to the bugman:  What is this? Is it a bee? How you want your letter signed:  ??

Dear ??, We had no idea where CH43 9AJ is located, but a web search produced:  “CH43 9AJ. Postal code in Birkenhead, England.”  This is a Sawfly, a non-stinging relative of Bees and Wasps.  Based on an image on NatureSpot, we are quite confident it is Zaraea fasciata, and the site states:  “Uncommon with most British records coming from England and Wales.”  According to UK Wildlife, it is commonly called the Honeysuckle Sawfly.

Letter 38 – Elm Sawfly

 

Subject:  Cicada wasp? Geographic location of the bug:  Hoquiam Washington Date: 07/21/2019 Time: 10:22 AM EDT Your letter to the bugman:  This wasp like insect was on my chair. In the forest of Hoquiam Washington. July 19, 2019. I did not see a stinger, it moved slowly, did not try to fly away. it was approx 1.5 inches long. How you want your letter signed:  Veronica

Dear Veronica. This is not a Western Cicada Killer.  It is a non-stinging Elm Sawfly. Thank you Daniel. We dont have Elm trees here though! Hi again Veronica, According to BugGuide:  “hosts include elm (Ulmus), maple (Acer), birch (Betula), willow (Salix), and basswood (Tilia); adults girdle bark on twigs.”  Additionally, lists of host plants are often incomplete and many species adapt to different host plants due to garden cultivation and species range expansion.

Letter 39 – Elm Sawfly

 

Subject:  Cool flying insect Geographic location of the bug:  Kilchis Point, Oregon Date: 08/05/2021 Time: 08:54 PM EDT Your letter to the bugman:  This insect landed on a friend’s hat and just stayed. It was close to an inch long and quite robust. How you want your letter signed:  Sara

Dear Sara, The Elm Sawfly is a non-stinging distant relative of Bees and Wasps, and it is perfectly harmless. Wonderful! Thank you! We were leading a STEM camp for middle school girls when it appeared. We all got a good look at it and then gently moved it to some plants. I appreciate the help! Sara

Letter 40 – Sawfly from England

 

Subject:  What this bug Geographic location of the bug:  Nottingham England Date: 08/15/2021 Time: 08:33 PM EDT Your letter to the bugman:  Hi there, would you identify this little beast for me please? How you want your letter signed:  A Draycott

Dear A Draycott, This is a Sawfly and we identified it as Cimbex connatus on NatureSpot where it states:  “A very large (3 cm body length) sawfly, vaguely resembling a hornet but fatter bodied”  and “The larvae feed on various alder species. When fully grown, they are about 50 mm long and have a dark dorsal stripe all the way along the body. They generally feed between July and September, but may still be found as late as October.”