"Love this mistletoe. Why you should see how many girls kissed me today."

"This lousy mistletoe is killing my mesquites. They can't breathe." Let's you and I dispel old wives tales and seek the truth about this amazing parasite.

The Eniglish name mistletoe is said to have been derived from Misteltan (Mistel - different, tan - twig, referring to the difference between mistletoe and its host, the branch on which it is growing). Druids (remember Stonehenge?) believed that mistletoe protected its possessor from all evil, and branches were used by them to enter the New Year.

Scandinavian legend has it that Balder, their God of Peace, was slain with an arrow made from mistletoe. Later he was restored to life at the request of other Gods and Goddesses and the plant, mistletoe, was given to the keeping of the Goddess of Love. To honor her, it was ordained that everyone who passed under it should receive a kiss. This was to show all that mistletoe was an emblem of love and not that of hate.

Both of these ancient customs probably carried forth to our modem day ritual of hanging mistletoe over entry-ways and then kissing whoever enters under it. After a kiss is obtained, the kisser is to remove one of the white berries until they are all gone. A smart person buys several branches containing berries and when one branch no longer has berries on it substitutes another.

There are two distinct types of mistletoe found in Arizona: dwarf mistletoes found in conifers and the true mistletoe, Phoradendron californicum, found growing on Palo Verde's, acacias, and mesquites.

P. californicum is a perennial, evergreen, shrubby, photosynthetic, plant-parasitic seed plant belonging to the family Viscaceae. It has no roots and is parasitic on the stems of woody plants from which it derives water, mineral nutrients, and small amounts of the organic compounds carried in xylem sap. The wood of mistletoe has been found to contain twice as much potash and five times as much phosphoric acid as the wood of the host tree.

Mistletoe preferentially receives water during times of drought and wastes water by continuing to transpire even under water stress. This causes severe water stress in mistletoe hosts and is one of the main causes of vigor and dieback. P. califomicum is a "hemiparasite" as opposed to other true mistletoes. What this means is that it is able to make its own chlorophyll and is able to produce most of its own organic nutrients through photosynthesis and obtains little carbon from its host.

It has tiny scale-like leaves on long pendulous stems, in time attaining lengths greater than two and one half feet and forming dense bushes. It is dioecious (male and female flowers on separate plants). Its white flowers form in May and are inconspicuous. The berries which house the seeds ripen in December and are white to reddish. If you use the mistletoe outdoors you have got to be careful not to sow the seed. The fruit of the mistletoe is reportedly toxic to livestock as well as humans.

Green straggly, bushy growth of mistletoe hang from infested branches of the host tree. These branches and stems become swollen, with atrophy and dieback closer to the tree trunk than the parasite. Infections on the lower trunk are more damaging than infections in the upper branches.

It is very difficult to control. Recommendations are to prune out tainted branches one foot below the infected area. Do not forget good pruning practices. Never prune more than one third of the host's annual foliage. Perhaps cutting off the berries of the mistletoe will prevent it from spreading. As far as prevention, keeping a close watch on your neighbor's trees and alerting him to a problem as it grows is about all you can do.