Large clouds of pollen shroud the air above a forest of pine trees in Conthey, west Switzerland.

The footage shows pollen clouds being blown into the air by gusts of winds on May 17.

Huge clouds of pollen are released by pinetrees as gusty wind blows.
These trees are Picea abies , a.k.a. Norway Spruce , or European Spruce.
Depending on the altitude some of them are now blooming in the Alps and producing large amounts of pollen, and when it gets windy they get blown away in huge yellow clouds .
This was seen in the swiss Alps in the canton of Valais, from a mountaintop above the city of Conthey.
If you are allergic to this pollen it may be best to avoid hiking there for now.
The swiss national weather service publishes a map with pollen forecast https://www.meteoschweiz.admin.ch/home.html?tab=pollenprediction