Bob F wrote:
I have a plum tree that is in full bloom. It's fruit is vary large
reddish yellow plums 3" long when ripe. Usually, it gets a dozen or
two fruit on it, but one year I harvested 80 pounds of plums from it.

Here in Seattle, the spring has been cold and damp. There is no sign
of any bees. I am wondering if there is some way of pollinating the
tree manually, perhaps be tapping a branch from my neighbor's small
fruit plum or my italian prune trees against it's blooms. Does anyone
have any knowledge about this they could assist me with?

Plums are almost always pollinated by bees, there is little or no wind
pollination apparently. Some are self fertile, others are not and some in
between. The other trees might or might not be a pollinator for yours. I
don't know how you are going to transfer the pollen at the right time as the
flowers don't reach maturity simultaneously, although the numbers are on
your side as you only need a little pollen on each flower and only a small
proportion need to be pollinated to get a good crop.

David