Edit. After Black September's assassination of Israeli athletes at the Munich Olympics in 1972, Prime Minister Golda Meir okays a black-box operation to hunt down and kill all involved.
Yellow pollen is produced by evergreen trees, primarily pine trees, including spruce, true cedar trees, fir trees, larch and hemlock. Although yellow pollen looks like it could cause an allergic reaction, in reality it does not trigger allergy symptoms at all. It can stain the skin and clothing, however.
Citrus greening. Identification tip: Yellowing in just one section of a tree is characteristic of citrus greening. The cause is a bacterium spread by aphidlike psyllids. Symptoms include stunted trees, leaf and fruit drop, twig dieback and fruit that are lopsided, small and bitter-tasting.