To me that has the look of a fungus or gall rather than a scale. Does it scrape off easily with a finger nail?

I haven't tried to do that, but I'll go up the roof right now and check.

I detached it from the leaf and transferred it onto a white tissue. Here it is:

My question was really to establish if it came off easily and whether there was a soft creature underneath? If it didn't and there wasn't, then I don't think its scale.

It didn't come off easily, but I wouldn't say it was difficult to pry. Slight resistance is more like it. Underneath there was some reddish-brown powder but I didn't see any soft creature.

presuming you didnt plant it on the roof in a crack ...then it was wind blown seed ....

so why would it surprise you that disease and/or bugs might not be wind borne also ...

though i understand the dilemma of how a scale that seems to live within inches of where mom laid the egg .. could have gotten on the roof ... this is the base issue .... right? ...

how do scale move plant to plant ...

ken

The aren't any plants around that tiny poplar. About 30 feet from it there's some groundsel - totally healthy. No bugs or disease.

What climate area? Leaf looks like tallow tree rather than poplar.

It's not tallow tree. I'm familiar with it. Zone 9/10, early spring.

The bark is literally covered with those scale-like things.

I'm not convinced it is scale, which would come off easily. I think its a gall.

I believe it to be a scale insect, perhaps a dead one with the remains of a batch of eggs. The eggs of scale insects are typically red; the adult female dies not too long after she lays the eggs underneath her shell.

Any chance of seeing a pic of the bark with these things all over it?

Pics of the bark:

Closeup of the bark. One of those little bumps got detached when I broke the poplar's stem, and that's the reddish spot - where the scale/gall or whatever was before it got pried off the stem.

Pic of the whole plant:

Also, I noticed two more things this morning: There's some moss growing right next to the poplar, and there were a couple black ants crawling close to that poplar. Could the ants have carried the scales - presuming they're scales - up to the rooftop six floors high? It didn't look like it because the ants were much smaller than the scales, but do ants carry scale eggs? Are ants in the habit of carrying scale eggs?

Ok. Now I believe it's scale. Those pictures show its growth habit.

Thanks Floral. And it would be the ants, wouldn't it? I go up that roof several times a day to escape open-space office suffocation, and the sight of that poplar has been exercising me for a while.

Could well be the ants. Btw male scale can fly I believe but the females or eggs would need to be transported. As an aside, I think the building owners need to remove that sapling. It's a roof problem waiting to happen.

You're right about the roof problem. I've already killed one such sapling a couple years ago - cut the stem and dripped some neat roundup on the fresh cut. after the maintenance man just kept pulling it out and wondering why it's still alive.

This whole building is a problem waiting to happen.

I agree that this is scale. And, yes, ants farm scale and aphids for their honeydew. The ants probably have a nice nest somewhere up near that plant. Which reminds me - I need to sprinkle some DE on the ground under the Meyer Lemon to stop the ants from bringing in the aphids and scale.

Btw male scale can fly

==>>> no way ... learn something new every day ... go figure ...

i thought.. ants can milk scale for honeydew .. yes?? .. no??? .. but i never conceptualized them carrying them around ... double go figure ... lol ...

ken

No poplar produces those long drawn out leaf tips.

Which tree might it be? Zone 9/10, Israel. Whatver it is - it sows itself like a weed.

Edited to ask: could it be ficus religiosa, sacred fig?

^^ Not even slightly relevant to this discussion!!

Windberry, gardengal is right. This isn't relevant to this discussion, but not to worry! That open space office will kill me before roundup does.

Hairlike leaf tips do fit Ficus religiosa.

Thank you!

Could it be Brachychiton populneus which l believe is grown in Israel?

My first thought was also Brachychiton populneus. But moot point if it's to be removed...

Yeah, I'm just gonna say it.. ewwwwww! Apologies to Mother Nature but that scale on the stem in the second set of pictures are just so gross. I feel so sorry for the tree. Circle of life, I guess.

Brachychiton populneus is indeed quite common in Israel, especially as a street tree. Thing is I haven't seen any around here. I may be wrong, but I think BP's bark is different from this one.

This morning I took a photo of what remained of the sapling: I think there's a sacred fig not far away from here. I'll take a picture next time I sneak out.

Those lobed leaves do look like Brachychiton. It displays various different shapes.

Ok. Sneaked out and took pics of the tree on the other side of the street. Looks like a ficus to me. It doesn't resemble any of the brachychiton populneus I've seen.

Ficus religiosa all the time. Those extended drip tips are very characteristic. Besides, the seedlings like to grow in difficult places :-) https://www.google.ca/search?q=ficus+religiosa+growing+on+wall&source=lnms&tbm=isch&sa=X&ved=0ahUKEwjz4s3fx5vhAhXjCjQIHYsjABAQ_AUIDigB&biw=1522&bih=672&dpr=1.25

The large tree may very well be Ficus religious, but the half chopped off seedling on the roof has lobed leaves, almost maple like.

I agree the half chopped off seedling looks kind of puzzling, however I understand it is the same seedling as the one, easier to see, in the pic in the middle of this page.

F. religiosa leaves are almost round, sometimes heart-shaped. The leaf on the "roof" tree is almost certainly B. populneus. I have probably a hundred or more of them on my property, and can tell you that they have wildly varying leaf shapes, and certainly include those with that same elongated drip tip.

Brachychiton Leaves

Windberry, yes, it's the same seedling in both pictures. The seedling's leaves are identical to the tree's. In addition, I haven't seen any brachychiton populneus around here.

So how do we explain those lobed leaves?

Could stress affect leaf shape? The seedling produced about a dozen leaves last summer. It's in full sun all day long wihtout a drop of water, plus getting occasionally chopped and pulled at by various maintenance people.

Look at other examples of the fig and see if any have the same comparatively deep lobing. Also compare with brachychitons in the area. Check all features, including buds, stems and aroma.

Does the fig across the street produce a noticeable sap when cut? If it does, and the seedling does not then there is another difference right there.

I will, but all I can check is the fig across the street. There aren't any brachychitons around.

Edited to ask how far from the building should I check for brachychitons? What is the ants' roaming range?

" So how do we explain those lobed leaves? "

The thing is, there are no lobed leaves. Some kind of play of shade and light in the pic. It can be better visible in the enlargement of the pic of the seedling before it got damaged:

"Does the fig across the street produce a noticeable sap when cut? If it does, and the seedling does not then there is another difference right there. "

It can hardly be expected that there is any sap left in the seedling in its current condition :-) (see the last pic of the damaged plant)

The seedling looks as if it is still alive. If it is a Ficus it will produce white milky sap if you snap off a leaf.

"how far from the building should I check for brachychitons? "

If you ask with seed dispersal in mind that it may not matter that much, since seed dispersal agents for both, Ficus religiosa and Brachychiton populneus are birds (among other creatures), so the parent tree doesn't always have to be very close to the seedlings.

There is however one more point for Ficus religiosa, and it is the leaf venation. Compare:

Ficus religiosa leaves

https://www.google.ca/search?q=ficus+religiosa+leaves&source=lnms&tbm=isch&sa=X&ved=0ahUKEwj9mLyq26DhAhUCvp4KHftYDzIQ_AUIDigB&biw=1526&bih=672&dpr=1.25#imgrc=_

Brachychiton populneus leaves

https://www.bing.com/images/search?q=brachychiton+populneus+leaves&FORM=HDRSC2

Thank you, Windberry. This is very interesting. If we go by venation it's ficus religiosa.

I mauled that sapling so much that the few leaves it had left turned brown and fell. I'll wait till it sprouts new leaves to do a sap test as well.

It's a sacred fig. I snapped off a tiny new twig and some white sap oozed out.

Thank you for letting us know.