Desert Mistletoe flowers make up for their lack of visual appeal by sending out a very strong olfactory signal. The flowers were crawling with Africanized Honey Bees, several species of syrphids, and other flies. So obviously, both pollen and nectar were offered.
|Syrphid Fly nectaring and Honeybee collecting pollen
|Ripe Berries of Desert Mistletoe
|A Phainopepla male has claimed an Ironwood tree with a big mistletoe plant
|in early April these fledgelings are ready to move to the mountains
|piling all the seeds on one branch seems not be so good for dispersal of the parasite. Photo Ned Harris
|Seeds from a bird dropping on a mesquite branch. Notice the little red roots
|A Foothills Paloverde carrying a big mistletoe plant. Note that the branches above the parasite are mostly dead. But this is not the usual scenario.
Most old Ironwood trees are crippled and contorted with huge tumor like growths. The tumors seem to originate around old mistletoe infestations. I cannot say whether the mistletoe itself causes the tree to produce these growths, or if the trees are trying to encapsulate the parasite, or if the parasite has caused a secondary infection by giving tumor inducing bacteria an entrance point. At any rate, the tumors usually seem to start as 'brooms' which appear when all the sleeping eyes of a branch begin to grow in an unregulated fashion. Mistletoe is usually mixed in with these trees branches.
|'Broom' tumor on Ironwood. These usually contain mistletoe as well as Ironwood sprouts
While I don't believe that mistletoe in natural areas should be managed (as many visitors to our parks request), on our own land where we enjoy a very limited number of old, big desert trees, we try to break the mistletoe bushes off the host plants every couple of years.
|Seeds on a fence post
ps: I am surprised how few mistletoe plants are infesting the leguminous trees around Sweetwater in Tucson and the ponds around the Gilbert Water Ranch. While the banks are covered in mesquite and Palo Verdes grow along the paths, we found neither mistletoe nor Phainopeplas during our last visits.
pps: there will be a lecture about this topic at the Santa Rita Experimental Range this Saturday:
Too bad that I have an art show in SaddleBrook this weekend and cannot go!