By Jeff Floyd
Certified horticulturist and arborist
It’s Christmastime and all the plants are resting in preparation for a busy new year. But look up into your trees a little more closely. They may not have it so easy. They always seem to be under attack. Wood-destroying insects, fungi, and bacteria work their way into them through damage caused by lawnmowers, pruning cuts, and little Johnnie’s camp axe. Those critters are after the hard-earned sugars produced by photosynthesis. Neighboring plants aren’t so friendly either. They compete for space and even slurp up all the water and nutrients. But one pest takes it a little too far: mistletoe.
That’s right, the cute little green plant with the fat leaves and the shiny red ribbon is a tree killer. Oh sure, it looks all sweet and innocent hanging from the door frame this time of year. But don’t be fooled. It has sinister motives. Ok, so tree killer may be a stretch but it’s certainly a nuisance. Even botanists as far back as 160 years ago knew its true intentions. They chose the perfect scientific name for it. Phoradendron, or ‘thief of trees.’
Mistletoe is a crook, digging its grubby little “roots” under the bark and stretching them into the syrupy veins to sip on nutrients trees count on. Sometimes, tree branches think they can outsmart the green bandit by sacrificing themselves to save the rest of the tree. Eventually, the branch dies and the sugars stop flowing. Not a bad idea!
If mistletoe can’t get the sugar, then it’ll die, right? Wrong! Not immediately anyway. Mistletoe is an obligate hemiparasite which is a fancy moniker botanists came up with to make the rest of us think they’re smart. It means mistletoe can produce its own food, for at least for a little while. And it will also produce lots of seeds that drop onto lower branches and grow up to be big mistletoe pests.
Its fleshy lime-colored leaves use sunlight, just like tree leaves do. Turning carbon and water into sugar and oxygen. Only those ain’t tree leaves. Oh sure, they look like tree leaves and that’s exactly what mistletoe is counting on. But if your Cedar elm appears to be leafed out this late in December, something’s not right. The same is true for Red oak, mesquite, and even pecan trees. Those trees shouldn’t have anything that resembles green leaves on them right now.
If you see mistletoe in your trees, the best gift you can give them is to cut it out. But not yet. Stay on the couch until that third slice of pumpkin pie has settled. Or was it pecan? Who can remember these things? Just hang tight. After the New Year I’ll tell you exactly how to get that self-invited house guest to stop taking groceries from your sweet innocent tree; you know, the one that keeps dropping acorns in the pool. Merry Christmas!
