On Wed, 19 May 2010 12:28:01 -0400, "
wrote:

Prof Wonmug wrote:
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?

It seems very odd that it is in the shape of the tree's shadow.

Yeah, that's what I thought, too.

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.

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

Have you tried brushing or washing it off?

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