seems that mugo's are prone to attacks of things. I had something simarly horrible last year. Yours sound different, but just as bad. maybe another kind of sawfly.

http://forums2.gardenweb.com/forums/load/shrubs/msg0908091524456.html

aphids come in all colors unfortunately.

According to the latest UMass Landscape Message:

"European pine sawfly caterpillars are active. Inspect host foliage (primarily mugo pine) for the yellow, blocky patches, which are the eggs embedded within the needles or look for the tiny dark-colored larvae clustered at the needle tips. In most regions of the state, the caterpillars are now active. This pest feeds voraciously and grows rapidly. Needles will be consumed down to the stems. Needles with eggs or stems with larvae can be pruned away and destroyed when this pest occurs in limited numbers. Otherwise, treat the larvae with a product that contains spinosad or use one of the registered pyrethroid insecticides. Very small larvae can be treated with insecticidal soap effectively."

Claire

go to the latest UMass Newsletter, posted always by Claire, and you'll see the perfect description of your critters. It also talks about controls. Better hurry, because as you've seen, they can strip it in short notice.

HOnestly, that"s the only reason I don't have mugo pines anymore. They were infested every season and look just terrible. Some deciduous shrubs are still passable during and after an insect attact, but conifers/evergreens no way.

I learned my lesson in the late 80's! I vowed never again to plant mugo pines. In the 90's I lost a beautiful blue Mongomery spruce to a similar insect....for the life of me I can't remember the name, but they form oval tan colored patches on the inside stem during the winter, then erupt in the late spring.

I'm so sorry for your loss.