Wierd stain on new driveway

[Prof Wonmug]

A few weeks ago, we replaced the 40-year-old asphalt on our driveway with pavers. Yesterday afternoon, when I came home, I noticed a large stain that I am 99% positive was not there when I left in the morning. The pavers are grey. The stain is an orangish-brown (more brown than orange).

The stain is roughly the same shape as the shadow that would be cast by the tree in the neighbor's yard if the sun were directly overhead. The tree looks like a birch or beech tree.

It looks like something is dripping off that tree. Could it be sap? I stood under it and didn't feel anything and I can see anything. The stain is dry, not sticky. It's also very even, like it was painted oon, not speckled, so if it dripped, it was something fine. PLus, I;m pretty sure it happened in just a few hours.

Does anyone have any idea what this could be and, more importantly, how to remove it?

We never saw anything like this on the old asphalt driveway, which was also grey.

I can take a photo if that would help. Is there some good place to upload it?

[mike]

Some fertilizers contain components that can stain. Have you or your neighbor been spreading fertilizer?

[mike]

By the way, what kind of tree is it? I wonder if the sap has a high tannin content.

[mike]

Nevermind. I forgot that you already mentioned your guesses on tree species.

[Prof Wonmug]

We have not -- especially not in the exact shape of a tree shadow. I don't know about the neighbor, but they don't have a front lawn, so I doubt it.

[Prof Wonmug]

Didn't I say that it looks like a birch or beech?

[mike]

Yes. See my previous retraction.

[Mark]

did it rain lightly during the day?

Mark

[norminn]

It seems very odd that it is in the shape of the tree's shadow. Wonder if pollen could do that? Has the tree been blooming? In Florida, we get so much oak pollen that the yellow powder can be seen on cars and pavement. Have you tried brushing or washing it off?

[Bob F]

Aphid (or other insect) "dew"?

[Prof Wonmug]

Dang, I forgot to mention the rain. It didn't rain that day, but it did rain a little the night before and some of the previous few days.

I am 99% certain that the stain was not there at about 9:00 am when I went out. I think it happened between 9:00 am and 5:00 pm.

I just went out and took a few photos. The driveway is still in shade, so they aren't that good.

I felt the pavers. They are dry (not sticky). I also felt the tree. It is not sticky and does not appear to be dripping anything.

Puzzle...

[Prof Wonmug]

Yeah, that's what I thought, too.

No blooms. The leaves have been out for weeks. I can't see any pollen.

I tried brushing and sweeping. No effect. It's definitely a stain. I haven't tried washing yet. Not sure what to use.

[Prof Wonmug]

I called an arborist and that's what he said. But all within a few hours? He's coming over to take a look.

[Bob F]

Go out and watch the space below the tree in full sun with a dark background. Sometimes it will look like a fine rain if you have a bad case of aphids. Or, look at the leaves for the bugs.

[norminn]

You might call your county extension service if they have horticultural experts...some kind of pollen or insect droppings?

[Joseph Capgras]

Well if it looks even remotely like the Blessed Virgin, call your local TV news guy, then get ready to start selling tickets and souvenirs...

[Prof Wonmug]

You know, I think I do see a face in there. Or it may just be a giant Rorschach test -- but then I thought all of those looked like beavers.

[Oren]

Post them at tinypic.com and provide a link here in the group.

Where the pavers from the same lot?

[Stormin Mormon]

I'm nominating this one for best idea of the week.

[Paul Franklin]

Any chance that the rest of the pavers that were not in the shade just dried more thoroughly from the sun and what you are seeing is higher moisture in the ones that were shaded? A paver that feels dry to the touch can still have higher moisture content. And moisture content definitely affects color. Try drying one with a heat gun or hair dryer?

Paul F.