Aphids and more aphids
>> Saturday, January 22, 2011 –
aphids,
insects,
microscopy
It's that time of year again when anybody overwintering outdoor plants inside starts having problems with various insect pests. The critters are there from the start, but it takes a little while for their populations to explode, which is when they first get noticed -- at least by me. In this case, I've got aphids on a couple of small potted bamboos.
Aphids normally won't do too much harm to bamboo and don't seem to like the mature leaves, but these are concentrating on the new, not-yet-unrolled leaves. The choicest, most tender parts of the plant (of course).
I first noticed them by their droppings on the surface of the leaves:
The shiny droplets of sticky, sap-like residue look at first like water left over from my misting of the plants, but they don't evaporate.
Taking a look higher up the plant, you can see some of the little trouble makers:
You can also see their discarded skins, left over from moulting (the only way that insects can get larger is to shed their hard exoskeletons when they outgrow them):
I found a few on the underside of a leaf too:
Looking around my plant table, I noticed that the variegated ivy really has wet-looking leaves:
Upon closer inspection, this plant is loaded with not only moulted shells, but live insects too. I had this problem last year too so I should have been checking this plant frequently, but I forgot.
Are these aphids too, or something else?
Pretty hard to tell, but I think we need to take a closer look, so time to get out the microscope:
That's what the ivy bugs look like at 40x magnification. The bigger ones are moving around a bit, while the smaller juveniles are completely still.
That's with lighting from the top instead of from below. I don't know if these are aphids or not. How about a closer look?
That's 100x. Ok, they are aphids, although I don't know the species (and can't find it on BugGuide.net). The two "tubes" protruding from the back near the tail is found in most aphid species, and that's where the sweet "honeydew" that ants collect is produced. No sign of ants yet thankfully.
Let's take a look at the aphids that are on the bamboo for comparison:
Ok, that photo isn't going to tell us too much, but you can see that the body shape is a little different. (I really like this photo!) A closer look, with some better lighting:
Much different than the aphids on the ivy! No back "tubes", red eyes, completely different color body. There's no question these are two different species of aphids. I wonder why there aren't any "tubes"?
As much as I enjoy taking close looks at these insects, they're still pests that are feeding on my plants (sucking their juices), and they need to go!
I'll take care of them soon, possibly tomorrow.
Wow, what great photos of aphids! Now that I know what they look like up close, I must say I don't like them any better :-).
We have three potted bamboos in our back yard that are infested with aphids right now (Castillon, Castillon Inversa and Temple) and I sprayed them with insecticidal soap yesterday. You'd think that after the recent frost the aphids would be dead, but they aren't.
To make matters worse, we have sooty mold developing on honeydew excreted by the aphid, which is really unsightly. I need to step up my anti-aphid regimen before their populations explode!
:: Bamboo and More ::
Outdoor aphids I almost never worry about, unless it's a small potted plant with a large number of insects.
I actually like finding plants with lots of aphids on them, because I'll catch ladybugs (lady beetles) and release them there to watch them eat. Also, these are good plants to release baby mantises on too. =)
Alan, we keep finding lady bugs in the yard but never enough. Aphids are a real problem in our area until early summer when the heats seems to do them in.
Some trees in town are infested so badly that the honeydew drips on the cars parked underneath them. You can imagine the mess!
Alan, how did this turn out? I am a new homeowner and just planted 3 Golden Goddess along our fence to make a privacy screen. They were so happy and fluffy until I noticed the ants crawling all over the mold at the nodes...the telltale signs of aphids :( Have hit them with soapy water and pruned back a lot of the gross stuff, but I don't want to lose the plants!
The insecticidal soap took care of them. A second application after a few days really helps. On large outdoor plants, I'd probably use a really strong spray of water to blast as many of them off the plant as possible. Do this every few days and you should the population down quite a bit. If the plants are smaller you can do some insecticidal soap too, but you'll probably be hitting some beneficial insects too. You might want to try releasing ladybugs (ladybeetles) too, although there's some debate as to their use.