A phenomena

We were having lunch yesterday when I noticed this yellow/green plume being 'released' in various areas of the predominantly pine covered hillside.

Thought is might be a fire but then the colour was wrong and fires make a noise. This was silent.

Different parts of the hillsides had these releases. The only thing we could think of was a massive pollen release by the pine trees. The timing would be right. None the less not something either of us have witnessed before.