Attraction to eucalyptus

[runnr]

Curious, was is the attraction of monarchs to eucalyptus? I have heard of this but never got a clear explanation. We happened to go camping along the central California coast in Carpinteria and apparantly monarchs sometimes cluster there in the local eucalyptus trees. We stolled along a nearby eucalyptus grove but saw no monarchs. I did however see a couple flutter throught the campsite (monarchs, not eucalyptus). Is it the height of the eucalyptus? The photographs I've seen were of solid clusters of monarchs in eucalyptus branches, supposedly trying to stay warm.

[Mona Miller]

Strictly cover. Most of the historically natural trees have been cut down due to development. Earlier they were cut down to build railroads and houses. Cypress, pines, oaks were the historical species.

[Paul Cherubini]

The monarchs generally prefer the tallest clumps of trees available in any given landscape and although there are still gazillions of native pines, oaks, and sycamore trees along the California coast, the Australian eucalyptus towers over all them and so the eucalyptus is a more prominent landmark, hence the monarchs notice them more readily. There are some native cypress, redwoods and douglas firs that are almost as tall as the eucalyptus, but they often grow in sections of the coast that the monarchs consider excessively foggy and windy for long term clustering; e.g. Point Reyes National Seashore, Golden Gate Bridge area, all of San Francisco, coast of San Mateo county, etc.