Wednesday, May 3, 2017

Spruce Pollen

When I arrived at work this morning I noticed an American Robin (Turdus migratorius) fly into one of the spruce trees that line our parking lot.  As the robin disappeared into the tree a cloud of dust appeared.

Was the robin a magician using smoke to distract its audience?

No.

The spruce tree was heavily laden with pollen and the impact of the robin caused a pollen release.

A close examination revealed that the lower branched of the spruce trees are covered with male cones.  Male cones produce pollen and then fall off the tree once their job is done.



These male cones release pollen in huge quantities any time they are disturbed.  That disturbance could be a bird, the wind, or someone (me) hitting the branches with a stick to trigger the release of pollen.

First up is a native White Spruce (Picea glauca).


And here is a non-native, but commonly planted, Norway Spruce (Picea abies)


For good measure, I took a number of still photographs of the pollen as it was released.  The first picture shows the exact instant the stick hits the branch (of a White Spruce) and the whole sequence took less than 1 second to photograph.


 


 






The goal of all of this pollen is to float through the air and find a female cone.  Usually spruce trees have their male cones on lower branches and their female cones near the top of the tree.  This is to avoid self-pollination.  Although spruce trees can self-pollinate.  It is preferable that they exchange genetic information with other trees.


With this much pollen flying around, it's no wonder that my allergies are bothering me.




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