Imagine my surprise to see this mugho pine with sections of branches with needles missing.
But as you move closer, all of a sudden the pine seems to move. The sawfly larva (not really true caterpillars) are clustered together on the tips of the pine, although usually not right at the tip. When they are disturbed, they seem to rear up on their leggs. But they do this in unison - like a wave at the hockey arena.
These little creatures can chew off many needles from Austrian and Mugho pines in a short time if they are not treated with an insecticide.
a closer look at the larva
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