Hi, I wonder if anyone has noticed anything like this. One of my seedling areas is chock full of wasps, of the yellowjacket type. They seem to be only interested in this one table, which is in the heaviest shade, but curiously there are no wasps on the next table, or underneath, including any of the pots next to the table. There are literally hundreds of wasps -- I even got stung the other day -- but I can't see any signs of a nest. At first I thought they were after mites in the soil, but as it happens over the last couple of days I up-potted many of the seedlings from cells to individual godets, and the frequency of wasps is unchanged. I could imagine they're after water, but it doesn't make much sense that there would be none on the next table over, not even a foot away. Could they be nesting under the pots, maybe? You can see there's a grating keeping the pots above the table, but the clearance under it is quite tight. I can see wasps sometimes crawling under the grating, too.
So, was just looking at some other seedlings, many meters away, there were also some wasps, though not nearly as many.
I see the magic word from the tag - saccharinum (sugar). Could it be, that A. saccharinum smells attractive to wasps or maybe oozing some sugary sap?
They also like water when it is dry, I don't know if irrigation water can accumulate under the grating, even temporarily, and they are dining and drinking in the same joint...
There used to be lots of wild bees that would come on the soil of my pots, but I haven't seen nay so far this year ;-( It was obvious they were looking for a drink, though they might have found other things there, but I haven't seen wasps behaving this way. Probably not.
I saw you were still dealing with them, D. By this time of year, they're mostly off of the maples, either eaten by predators, heat, what have you. We do still get some in the garden, but they seem to prefer long stalky thinks like wormwood and nettles. Still, I thought they could be after mites in the soil, which would be good. But seeing them in the small pots with fresh substrate sort of blows that theory, unless the bags of composted bark have mites in them... I don't mind the wasps as such, if they'll let me get on with my business without getting aggressive! This seems unlikely, as there are few saccharinum, and lots of maples (and other plants) that aren't very sappy. There's a guy who recommends dosing seedlings with sugar; I can't imagine the ants, wasps etc that that would bring... This seems like the best theory to me, it's possible that the table has a bow to it under the grate, which others don't. They warp differently depending on age. The other table I saw them last night drains completely and there is no grate, but the pots could still have been moist. Still, you'd think they'd enjoy pots on the ground too!
Aside from sugars and carbs they are drawn to protein and the smell of meat or fish. Are you using fish, bone, or blood meal fertilizer? Or possibly fertilizer containing molasses?
That all makes sense, but no. Unless osmocote smells, in which case it should smell everywhere. Although now that you mention it, it could well be a smell coming off of the partially composted pine bark. This is straight, usable in organic, so presumably no "chemical" composting accelerant, I did notice a distinct smell when the bags first arrived. It's faded over time, but the wasps may well still smell something. It would make sense, being organic, that they would have used "natural accelerant" like, fish meal, or ground chicks, or what have you. What's more, the table in question does have the highest ratio of straight substrate, because there are a lot of non-maple seedlings where I didn't waste rock in the mix, it's just bark and perlite. This could explain it! Thanks. The wasps are multiplying, and getting more aggressive. They've moved to some other tables, and they don't like being sprayed with a hose, either. There are a few wasps nests around, and they generally aren't bothersome (and serve a useful purpose), but these are starting to be quite annoying.
You have a species that looks generally like european hornet gnawing the wood pieces on top of your pots to make paper for the nest wherever it is - get rid of these pieces and the source of attraction will be gone. At my previous habitation these and/or yellowjackets (my region has both) used to gnaw a neighbor's old unpainted wood fence for the same purpose. This activity could be heard yards away from the insect doing it each time. As in it was as noticeable as a gnawing rodent inside a wooden wall - when first becoming aware I'd hear all this noise, walk over to the fence to discover the source was instead this little bug.
If you get stung (fingers crossed you don't) pour white vinegar on the sting area immediately and the vinegar will quickly neutralizes the venom (taking away the pain almost instantly). I learned this in the Bahamas when I unfortunately got stung by a nasty tropical wasp (makes the limb that the sting is on feel like it's on fire). In my panic a local quickly poured white vinegar on and the pain was gone in seconds. Since, I've used it on yellowjacket stings with great success. Kids go from screaming bloody murder to back playing like nothing happened within a few minutes. If you do it fast enough you don't get any swelling either. The quicker you do it the better. I've had good luck with this trap. Don't fool around with bait, just pour cola in the top chamber and hang it up. It's called the RESCUE! W·H·Y® Wasp, Hornet & Yellowjacket Trap
