Disease on my conifers

Im relatively new to the art of Bonsai. I have a white powder on several of my conifers. What is it, and what should I do?

1. Is it only on your bonsai, or is there any on trees in the neighborhood?
2. What part of the tree is it on?
3. Can you post a picture? A close-up would be great.
4. How long have you had it?
5. Which conifers is it on?
6. Have you consulted your local agricultural extension agent?
7. Are your trees in full sun?
Iris

Its powdery white and its only on the evergreens, like japanese black pine, scots pine,etc. The location is on the branches, not all of them. I have them in my back yard which have other trees. I dont see it on the other trees. All of the trees are in the sun all day. I have dawn redwoods right next to these evergreens, but they or the other trees dont have this white powdery looking substance. I can post a picture tomorrow.

Maybe move the bird feeder to the other side of the house? Seriously though ,I hope for your sake that birds might be the cause. I am not sure if the diluted lime surfer is recommended for evergreens in the "dormant" season.

if the white is actually a very very pale green it is algae growing on them - if so not enough air movement and too much moisture. Another culprit is foliar feeding fish emulsion if you do that.

or it is snow

cheers Marcus

The powder could be pine pollen. Did your pines grow pollen cones?

Immature pollen cones:


Mature pollen cones:


They really do produce a lot of pollen if you don't pinch them off.