The
pollen sacs on this Scots (pronounced "Scotch")
pine tree are really modified needles. When the pollen
sacs fall off, a gap is left on the stem between the
needles on the end and the longer needles (see photo).
This contributes to an undesirable twiggy appearance.
In
Nebraska, you'll see pollen sacs in May and often
times on trees that are under stress from such things
as drought.
