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Fungus gnats or WINGED ROOT APHIDS???

GeorgeSmiley

Remembers
Veteran
The gnats like to lay their eggs in the destruction and rotten remains of the aphids dinner so they appear to be co morbid. They all bring infection, bac,vir,fung
 

spleebale

Member
Looking closer at those photos I can clearly see a difference between the two like you said.

THANK you. SO I'm not the only one who can see these clear differences.

The bottom bugs have one particular "feature" that makes me think they are indeed the same bugs as the top pics. The translucent nature of the rear end and the legs. It is also evident in the rather "new" and undeveloped appearance of the wings compared to the first bug.

The legs on the bottom bug are very translucent while the legs on the top bug are mostly solid/opaque. The abdomen on the bottom bug is nearly translucent while the abdomen on the top bug is opaque and clearly quite heavily armored. See, other people can recognize differences between them as well!

"It is also evident in the rather "new" and undeveloped appearance of the wings compared to the first bug" - You are reading into this (extrapolating information) BASED on the assumption these are the same bug and using that information to corroborate your assumption. What you assume to be "new and underdeveloped" I observe as being far smaller without the apparent iridescence (which could simply just be the angle).

I don't know why I am wasting my time on this, but I spent my morning going through 10 pages of Google images on fungus gnats (since there are no closeups of a winged root aphid even available other than [presumably] the one peregrinus has posted: Thanks, PG! YOU ROCK!)

Every single gnat - EVERY SINGLE one - shares ALL of the features I have pointed out about the bottom critter- though there is variation in the abdomen size, it is NO WHERE NEAR the variation we see here. None of the abdomens have thick exoskeletons on them (making the gnats MUCH lighter and contributing to their mosquito-like lazy flight). NONE of the gnats have wings that extend significantly beyond their frame - all gnats wings are shorter, ending just after the abdomen, making their flight far less powerful (as observed). While ALL of the gnats have the pronounced separated thorax (where the thorax is clearly a hard exoskeleton and the abdomen is clearly NOT armored with a thick layer of chiton)

ALSO: The iridescence of RA wings can be readily observed with the naked eye (their wings often catch the light) and the top photo just HAPPENED to capture this phenomena where NEITHER of the bottom ones did. In keeping with this, there was almost no iridescence captured in the fungus gnats photos or illustrations - nothing that could compare to the striking iridescence of the RA wings that was easily captured in both shots of the RA.

Note ALL of the thorax structures on gnats - it always looks the same; a hard, boxy structure that is easily distinct from head AND abdomen where all the legs are attached. This is NOT what we see in the top photo critter.

At this point I can't WAIT for an entomologist to get on here and end this, even if I happen to be wrong (which I would bet SERIOUS money against at this point).


images


images


fungusgnat.jpg


FungusGnatAdult_225x232.ashx


As for these sort of "contributions":

those in the pick a page or two back are most certainly fungus gnats not root aphids water with bt a few times and be done with it. your lucky there only gnats.

Please offer some sort of reasoning when attempting to throw your lot in to settle a dispute, so everyone can be satisfied that they have the right answer. Indicating to us that you are satisfied that YOU have the right answer without providing your reasoning does no good for anyone (unless we are all just to assume you are right all the time). If you have not read the information pertaining to the subject already (as you did not respond to ANY of the points I made about obvious visible differences between the two) then you are not helping those who have more information by telling them you know what's what.
 

spleebale

Member
Ok folks: after getting frustrated by people being SO SURE that these are both just gnats and are certainly the SAME creatures, possibly in slightly different stages of life... First I did the Google search to show you all the other gnats. Then i did a bit of Photoshop work to make the pictures more apparent (orienting them in the same direction as each other and as all the other gnats, making the ONE ROOT APHID stand out like a sore-elephantiasis-thumb).

Note: No image modification was done other than rotation, mirror-flipping and addition of graphics/text.


picture.php

^ ^
| THIS IS A FUNGUS GNAT. |


picture.php

^ ^
| THIS IS AN ADULT, WINGED ROOT APHID. |




So... you officially got me to "waste" the whole first half of my day, which sort of peeves me, since I have TONS of grow work to do, but at least I have put this bad-boy to REST.

No more "those are the same" or "those are gnats - just use Bti"
- and now Peregrinus and others can be certain about what those fast-flying little buggers that run around really fast actually are (as long as they have a good 50X+ scope! - but take my word for it; if they don't behave like gnats, they ARE NOT GNATS!)


So, to Eatmo: thank you for being a free-thinking individual and looking for what I was pointing out. To Peregrinus: Congrats! You have the VERY FIRST high-resolution photograph of a winged root aphid on the web! I am sure this will be useful to THOUSANDS of viewers, even if you never realize it. THANK YOU for furthering our understanding and knowledge. To all the nay-sayers and people without eyes or who were too quick to assume: how's the crow?
 

spleebale

Member
Here: I have put the two photos together in one image to help people look at both at one time. (Perhaps it was because of people's resolutions; they could not see them side-by-side without scrolling... or perhaps they just forgot what one looked like as soon as they switched focus... here they are all in one view). This will also help people who may find the joint-image through Google images looking for just one or the other.

picture.php


[Fungus gnat and root aphid]


Top distinguishing features upon close visual inspection:

-Fungus gnats have a classic "bump" in their body (their thorax) which gives a curved appearance to their profile.
-FG wings rarely extend significantly beyond the end of their abdomen
-FG abdomens are generally the narrowest area of their body.
-FG legs are not typically much longer than their bodies.

-RA wings extend well beyond the end of their abdomen and tend to be larger in general and more iridescent (often visible with the naked eye when they land or emerge from substrate)
-RAs have very long, mostly opaque legs that often well exceed the length of their bodies. (The most conspicuous aspect of RAs is visible with the naked eye, being their ability to run very fast with agility WHEN IN WINGED FORM - this is due to their strong, long legs.)
-Most of the RA body is dark and opaque (where the gnat abdomen is translucent; much of its body is to some degree). If you can put your random "flier" on a surface that is lit from below it will be apparent whether it is a gnat or an RA by whether or not it lets light pass through its body. (An overhead projector may be ideal for this, as looking into the light may make it difficult to look at the bug).
-RAs have a comparatively tiny head (relative to their body size and compared to FGs)
-RA heads tend to stand away from their bodies more conspicuously as the RA appears to be one large, roughly cylindrical body with one tiny little head, rather than three appropriately proportioned and connected pieces (head, thorax, abdomen) as in the FGs.

The easiest way to tell, interestingly enough, is not with a scope but with the naked eye (if you can obsrve them for a few seconds/go after them but not kill them right-off) - if they fly like mosquitoes, they are gnats (they are easy to clap, easy to approach, easy to kill on windows, plants etc.) if they run around, flick their wings a lot, look really "busy" and motivated, fly really strongly, are hard to clap and are aware of your intent to kill them - They are RAs. This is pretty much always the case, and once you become familiar with each by watching them for a few minutes collectively, they are pretty easy to distinguish.

Also: RAs reproduce much faster than fungus gnats and tend to produce much greater population explosions. If there are suddenly tons of fliers and more keep coming, they are almost certainly RAs. Gnat larvae are VERY susceptible/vulnerable to Bti (it almost always takes them out within a week if you apply it with consecutive watering on everything) such that fliers are reduced very quickly and are eliminated within about 10 days. If this is not happening and more fliers keep coming, they are almost certainly RAs, which are mildly susceptible to Bti at best (requiring expensive liquid Gnatrol or Vectobac or bulk Bti powder to be effective).


Also: I made the mistake I kept warning people against: the root aphid pictured above is clearly distinct from the Tank-Beetles:

attachment.php

"Tank-Beetle" Root Aphids

The root aphid in Peregrinus's photos looks a lot like the most advanced stage of the ones I had, however, which I identified as "crabs." I am not sure if PG has confirmed a crawly-type yet (or seen a crawler).

-WB
 

GeorgeSmiley

Remembers
Veteran
Wow, I see what you mean.... aren't pics great? I actually SEE what you mean, not from the originals but from your hardwork.

I googled "Flying Aphid"

I see the similarities. I had one of those super fast runners that ran right up thto the bottom of a leaf and watched me.... yeah actually watched me. I refused to believe it was a gnat since it was walking.
 
I'm still very confused. The fliers I have do act a little differently than the gnats I have seen before. Also I do see the iridescent wings from time to time but only on the containers, not out about. But every flier I have caught looks like a gnat. This is with only a 10x glass. I cannot find my 30x and I cannot afford to buy another. I also have never seen a non-winged aphid, "tank beetles", or "crabs" in my garden. So yeah I'm very confused. These are slightly bigger and stronger but do not have the longer wings as far as I have seen with 10x magnification. Also no armored bellys.
 
Back on track.....

From http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7404.html

DAMAGE
Low to moderate numbers of leaf-feeding aphids are usually not damaging in gardens or on trees. However, large populations cause curling, yellowing, and distortion of leaves and stunting of shoots; they can also produce large quantities of a sticky exudate known as honeydew, which often turns black with the growth of a sooty mold fungus. Some aphid species inject a toxin into plants, which further distorts growth. A few species cause gall formations.

Aphids may transmit viruses from plant to plant on certain vegetable and ornamental plants. Squashes, cucumbers, pumpkins, melons, beans, potatoes, lettuces, beets, chards, and bok choy are crops that often have aphid-transmitted viruses associated with them. The viruses cause mottling, yellowing, or curling of leaves and stunting of plant growth. Although losses can be great, they are difficult to prevent through the control of aphids because infection occurs even when aphid numbers are very low: it only takes a few minutes for the aphid to transmit the virus while it takes a much longer time to kill the aphid with an insecticide.

A few aphid species attack parts of plants other than leaves and shoots. The lettuce root aphid is a soil dweller that attacks lettuce roots during most of its cycle, causing lettuce plants to wilt and occasionally die if populations are high. The lettuce root aphid overwinters as eggs on poplar trees, where it produces leaf galls in spring and summer. The woolly apple aphid infests woody parts of apple roots and limbs, often near pruning wounds, and can cause overall tree decline if roots are infested for several years.
 

RetroGrow

Active member
Veteran
I really, really, really hate root aphids.
I wish there was a way to make them suffer before I kill them.
 

ItsGrowTime

gets some
Veteran
Spleebale,
I appreciate the effort but you seemed to take my thoughts on the pictures way, way too personally as if it's some slight if someone disagrees with you or offers alternate possibilities. Pardon me for "wasting your precious time" or whatever.

After looking at your explanation Im still not convinced simply because you point out the differences between the two pictures. That doesn't prove anything. What I don't see addressed is how the different stages of life could account for the variations. Putting up a couple red lines and saying "different abdomen!" is like comparing this picture:
catplr2g.jpg

with this picture:
swallowtail.jpg

and then saying they're different insects. Fwiw, both pics are different life stages of a swallowtail butterfly. It's an extreme example but I think you follow. I'm not saying you're wrong since I don't know for sure but I don't see how you're so sure they are different bugs. You're correct that we do indeed need an entomologist to know for sure what we're looking at. Otherwise we're all just making educated guesses.
 

ItsGrowTime

gets some
Veteran
And finally, here are the tiny "eggs" I'm seeing all over the lower surfaces of the "infected" plants. I know, I know, they look like spider mite eggs but I don't think they are. I have NO adult mites, no stippling on leaves, and I've been down that road before. Also can't seem to find any of these hatching or ANYTHING crawling on my leaves.
TTMpF.jpg

I really do love peregrinus' pics. I just checked some leaves and I also see these "orbs". They are actually visible without a scope since they reflect/refract light and make tiny "flashes" on the leaf. I observed them on both the top and underside of random leaves, both infected leaves and completely healthy leaves. These "orbs" were always there. Others have hypothesized they may be a fungus. Could they just be tiny but normal leaf trichomes? I wish we could get some people with 100% healthy gardens to check their leaves closely for these "orbs" so we know for sure if they are normal or not. My infected garden definitely has them! They are easily visible on the underside of a leaf with a 30x magnifier. Can anybody help by checking a healthy garden for these orbs?
 

spleebale

Member
GrowTime:

Yeah, I am VERY curious about what these are, though I am not certain we are all looking at the same thing - I think we should use something to compare size to like a grain of salt or a mite-egg (if you are lucky enough to have them). Mine are NO MORE than 1/3 the diameter of a mite-egg - so it does make me wonder whether they are the same thing as you are talking about/the one in PG's picture. I also have wondered if they could be trichomes, but I could not see a stalk under them - all of mine seemed to be right against the leaf surface (unless I just couldn't get the angle). Also - I am pretty positive a trich is WAY bigger than the orbs I have - I can see trichs with the naked eye and I am pretty positive I can't see these things without the scope - they certainly don't stick off the surface on a post as trichs are supposed to. Actually I am somewhat positive they (my "orbs") are not trichs as they often seem to be EVERYWHERE (almost every spot they could be in) and that would make the leaf very resinous -conspicuously so - if they were trichs. I do wonder whether they may be some sort of natural feature, however (plant-sweat?) because the ones I have seemed to be liquid formed on pores or something - they seemed like little tiny droplets, most of which were not full-spheres - seemingly because they were stuck to the leaf (like droplets forming on the ceiling - flat on the surface, round on the bottom) - but then some (only a few) seemed to clearly be full spheres, and often they would look more milky (like those in the picture). There is also the matter of the projections/hairs - are those cystolith hairs or something funky? Is there a reason they may be correlated to affected areas (as I would occasionally see patches of them where their bases all seemed to have a white residue around them - like you had poured milk all over them and let it dry). It could have just been residue from a foliar spray, but it seemed to only be in occasional patches (was not uniform or regular) and I kinda doubt that water would be able to settle around the base of those things, as cystolith hairs are extremely hydrophobic (if you poured water on the leaf in the photograph you would likely see it ball up in a droplet that took up most the picture).

Anyhow - more exploration into these "orbs" is called for - I wonder though if we are going to feel like dweebs when we find out that they are just some natural plant feature... Or we could be onto something. Once again, very good work, PG.
 
i have had root aphids just finished dealing with them those pics above are not the root aphids i had or have seen. they are aphids and have an aphid body shape(pear) and two visible antennae on there rear.
 
i think there are more than one species of root aphid or phylextherra(misspelled) mine were not like those in the pic and were a real nightmare destroyed a grow. in the end i eradicated them with pyrethrum/canola oil foliage and root drenches i did this 3 times every 4 days. the problem often is that even if you kill the root aphids you end up sometimes with root rot for that i use h202 hygrozyme and i allow the soil to dry root aphids and root rot love wet conditions.
 

Sickaluph

New member
I have been using the regular Bayer Tree & Shrub at about 5ml per gallon. I am now switching to the Citrus version, which I see has a lesser amount of imid in it.

How many milliliters per gallon are you guys using for the Citrus?
 

spleebale

Member
I will acknowledge that I am still not 100% certain that the bottom image is actually a root aphid. Reservations are based mostly on the appearance of the front and rear ends of the bug (the head seems much more detached than in other aphids (where you get the "pear" shape and the head seemed to be a continuation of the body) - also the eyes (the multi-eye, fly-look) does not remind me of aphid eyes at all. Further, the thing on its abdomen (little forked "tail") looks more like the classic fungus gnat tail-end than it does like aphid cornicles (parallel tailpipes emerging from opposite sides).

While it makes sense that they would develop a different, downward-facing head (to see better as a flier) and that the cornicles would no longer be necessary, I do not know that this is what happens - I will admit that it still seems uncertain why there would be two different winged forms/why they would still morph after developing wings.

That said, I am nearly certain that the bottom thing is NOT a fungus gnat (from ALL the differences pointed out), and that it IS the fast-running/flying, more-aware bug that emerges in droves far greater than fungus gnats ever do. Perhaps this is a third species that is also capitalizing on damaged plants/decayed root, but because of their similarities (size, reproduction/life cycle, areas of interest [roots]) to RAs and the fact that they are associated with RA people/problems and that they are pretty clearly not fungus gnats leads me to conclude that they are a form of RA rather than something else entirely that no one has ever heard of before that acts just like RAs, is the same size and comes in after an RA occupation. This is just the simplest explanation, though I will admit I do not have enough evidence to be certain that the bug is an RA.

The only thing I felt that I displayed clearly with the image analysis was how different the two bugs we were looking at actually are; I stand by that and still feel it is plain as day.

-WB
 

spleebale

Member
Sick:

Hey, I guess you don't have enough posts yet to have PMs

Why are you switching to Fruit and Citrus? It is just marketing; there is nothing better or safer about it for your plants - it will not be less harmful or absorbed less or wash out sooner. The only reason it says it stays in for less time is because it is less concentrated (they tell you to use probably 1/40th of how much imid the Merit tells you to use) - the more imid you use, the longer it will be around in the plant, the longer (and more thoroughly) it will control pests - period.

The more concentrated the product the less product you have to use to achieve the same imid levels, the less money it costs you. I think Merit 75 is the best deal if you are going to use a LOT, while Green Light T&S is the cheapest for the lower-concentration formulas. Fruit and Citrus is the way to give the most money to Bayer and to put the most other "inactive" ingredients (the solvent/emulsifier that the imid is dissolved in) into your root zone; this may be an additional deterrent to RAs and may kill fungal spores (as there is a bit of research on wetting agents killing zoospores), OR it may just be additionally harmful to your plant.

It seemed fewer Merit people mentioned the plant responding badly and more often reported the plants looking much better immediately. Also, the ONLY time my plants HATED the imid application it was a night-time watering of rock-wool mini-cubes planted in keg cups and I did half with Bayer CIK as usual and half with Bayer Insect, Mite and Disease control (it has imid too and I wanted to test out the "disease control") - the latter having far less imid than the C.I.K., I upped the dosage to compensate to the same imid levels as the CIK application. Those half of plants looked TERRIBLE the next day (all droopy like they had been sitting in water for days) and the others were nice and perky. There are two other chems in the Insect, Mite and Disease, however, but it just as easily could have been the high levels of the emulsifier/solvent as that is the substance you are actually giving them the most of with every Bayer application. Perhaps it would be good to look into what it is??? Just a thought.

-WB
 
I will acknowledge that I am still not 100% certain that the bottom image is actually a root aphid. Reservations are based mostly on the appearance of the front and rear ends of the bug (the head seems much more detached than in other aphids (where you get the "pear" shape and the head seemed to be a continuation of the body) - also the eyes (the multi-eye, fly-look) does not remind me of aphid eyes at all. Further, the thing on its abdomen (little forked "tail") looks more like the classic fungus gnat tail-end than it does like aphid cornicles (parallel tailpipes emerging from opposite sides).

While it makes sense that they would develop a different, downward-facing head (to see better as a flier) and that the cornicles would no longer be necessary, I do not know that this is what happens - I will admit that it still seems uncertain why there would be two different winged forms/why they would still morph after developing wings.

That said, I am nearly certain that the bottom thing is NOT a fungus gnat (from ALL the differences pointed out), and that it IS the fast-running/flying, more-aware bug that emerges in droves far greater than fungus gnats ever do. Perhaps this is a third species that is also capitalizing on damaged plants/decayed root, but because of their similarities (size, reproduction/life cycle, areas of interest [roots]) to RAs and the fact that they are associated with RA people/problems and that they are pretty clearly not fungus gnats leads me to conclude that they are a form of RA rather than something else entirely that no one has ever heard of before that acts just like RAs, is the same size and comes in after an RA occupation. This is just the simplest explanation, though I will admit I do not have enough evidence to be certain that the bug is an RA.

The only thing I felt that I displayed clearly with the image analysis was how different the two bugs we were looking at actually are; I stand by that and still feel it is plain as day.

-WB
like you suggested i think a second very similar species to fungus gnats but quicker and fast to develop none the less not an aphid species. the first pictures on the first page are the dreaded root aphids i have had pear shaped long round wings and green or black coloring also almost always on the move. i know the imid is the best way but i was able to eliminate them with repeated soil/foliage drenches of pyrethrum and canola some plants were badly damaged and were culled. the biggest mistake i made was letting them get out of hand and also overwatering which they love.
 

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