These are "grubs" or insect larvae. And, yes, they are VERY dangerous to plants as they eat roots and when they haven't any roots to eat, they ascend the plant stem. I have had these eat many Echeveria stem. This is why I treat ALL of my plants with imidacloprid granules in July and September prior to bringing them indoors for the winter.

Howard

This post was edited by bikerdoc5968 on Tue, Jan 20, 15 at 14:45

Thanks Howard. Well, sometimes, when repotting, i have this bad habit of re-using some of the soil from the plants i have just purchased. Just in case... if i'd removed them already, would the plants be alright? Or do they leave tiny eggs you can't see?

iane

The eggs have hatched into the larvae stage. These grubs will munch on whatever food they can find until it is time for them to metamorph into the adult insect... most likely some type of beetle. Could there be more eggs that will develop into grubs? Absolutely! If you want to use old soil, I would suggest placing it in a microwaveable bowl and zap it for several minutes.

Good info from Howard.
They look very much like vine weevil larvae to me, yuk! They are a European pest but are also found in the US I read.They can decimate a plant, and are commonly found in containers that contain a high %age of peat. They make ideal tasty snacks for my pond fish, lol.
Have linked a page for you to read .

Check for the adults and if you ever see any dispose of them in whatever way you can. Inspect the roots carefully for the grubs, not found eggs myself but obviously they were there at some point! If not exactly vine weevils, they are definitely a pest, so the sooner they are ridded the better. Happy squashing :)

Gill UK

Here is a link that might be useful: Evil weevil

Hi Gill, thanks for the link. It was very helpful. I believe I've seen something like this... it explains the notches on one of my echeveria's leaves (a cultivar that i only have one plant of, at that. Really annoying). The thing is, I happen to like insects (well, not exactly fond of squashing them) so i simply removed them. As for the larvae, i saw them in only a couple of pots. But i don't think I'm going to be reusing soil anytime soon Howard.

-iane

Hi, sorry for the blunt extermination idea! I too like many insects, each as a role to play I guess, but not when they destroy my treasured plants I'm afraid. They have to GO. Just hope yours have got a bad memory and don't remember their way back home :)

Gill UK

Oh Gill. That echeveria died :(

"I too like many insects, each as a role to play I guess, but not when they destroy my treasured plants I'm afraid. They have to GO."

The thing is -- i know this is the C&S forum and i will probably post this on another forum -- i have been having a lot of trouble with my coleus lately. I thought at first it was cyclamen mites because i couldn't see anything, only symptoms from the plants. The first signs i noticed were curling/ crimping of leaves and very stunted growth. Then the lower leaves started dropping. Some were yellow, some were really brown and dried. I finally saw actual insects a week ago and IDd them as leafhoppers (BUT i am sure they were not there before... i was really dreading that my plants were infected with the microscopic cyclamen mites). I started using my homemade soap spray -- which worked well before for the mites and mealybugs in both my succulents and ornamental plants -- until i realized that almost all of my coleus were affected (14 out of 16, how about that). Some of them were reduced to a few leaves and the bushiest ones were the worst affected (of course, if i were a bug, i would go for the buffet).

Well, i had little time nowadays to spray them regularly and I read that the other beneficials might be affected. I had noticed a few clumps of eggs and a small beetle (i love beetles most of all) so i researched first. The eggs which were on stalks MIGHT be lacewings, so i let them be. I spent one afternoon handpicking all the leafhoppers i could see from my coleus and i could still barely make myself crush them so i just drowned them all in alcohol (they have interesting blue green "blood"/ innards when they burst or are crushed). I hope doing so helped tremendously in decimating their population though i know that there are probably nymphs and eggs about. The beetle i let alone for a couple of days thinking it might get at the tinier leafhoppers. I also employed our friendly neighborhood spiders. I caught several from our allamanda tree and dropped them onto the plants. I was feeling clever about these steps. I mentioned before that i am fond of insects so i thought it was only just.

Tonight as i was looking at pictures of my damaged leaves (for documentation) i realized that the leaves had nibbles/ notches and so far, from what i've read, this was not consistent with leafhopper damage. I remembered you and compared a pic of the beetle with your link. Crap! It's that evil weevil! I went out instantly and picked it from where i had left it. Unfortunately, i stepped on it (accidentally, i swear) but it did not seem as spotty as the vine weevil.

Now, my concern is this. I use mainly fresh soil for my coleus. But there were some pots in which i recycled soil (i know, i know). I've read that the weevil larvae does the most damage... do you think it could be the main cause of my plants' sickly growth before the leafhoppers came along? Because i know that when a plant is in poor health, they tend to attract more problems and i don't think the leafhoppers are the first to blame. Some of my plants were really lush, with big leaves and vivid colouring and now a lot of them are dying :(

This is my first time to encounter an infestation of this scale so please forgive my wordiness.