We all know that deciduous trees—oaks, maples, and the like—lose their leaves in the fall. But what about conifers? They’re supposed to be evergreen! Should we be worried if we see lots of brown needles on our pines and firs?
As is frequently the case with questions about gardening, the answer is “it depends.”
For the past few weeks, my blue car has been yellow. Drifts of fine mustard-yellow dust cover our patio, our deck, and the floors indoors. I dust, and dust, and dust again; each time the rag comes up yellow. What is this dull yellow layer that covers everything? It’s pollen. More specifically, Ponderosa Pine pollen.
For those of us who live with pine trees, the pollen season is a yearly event as predictable as the throngs of Miller Moths currently beating themselves to death against our windows, and happening at the same time of year. Because we had a lot of rain at the end of last summer, 2014 is particularly pollen-y. All those trees, once dying from thirst, have a new lease on life, and they’re taking full advantage.
They’re adorable, with their short stumpy tails, tiny bodies and toddler-round tummies. They’re constantly active, hopping from branch to branch. Can you tell? Pygmy Nuthatches are one of my favorite birds! I love to watch them fly down to the feeder to grab a seed, then bolt back into safety before “hacking” (“nut hack” has become “nuthatch”) the sunflower shell open against a branch. Sure seems like a lot of work, especially compared to the finches who just sit there shelling and swallowing seeds as fast as they can.
Like so many other animals—dolphins and penguins come immediately to mind—Pygmy Nuthatches are dark on top and light underneath. This pattern helps disguise them from potential predators. Seen from above, their dark gray color blends with the ground (or tree trunks), while their white undersides are hard to spot against a brightly lit sky.
Last summer we took a drive to Granby, just outside of Rocky Mountain National Park. While I had heard about the Mountain Pine Beetle for years, I was unprepared for the extent of the devastation. Entire mountainsides were covered in dead and dying pines, eerily resembling New England’s beautiful red fall foliage. But rather than deciduous maples and other hardwoods, these were conifers, largely ponderosas. They wouldn’t be turning green again come spring.
Many of us who live along the Front Range of the Rockies have ponderosa or other pines on our property. They’re well adapted to our climate and soils, and very resilient. But in spite of their suitability for our area, there are two major problems that pines can encounter. I discussed mistletoe last December. The other major cause of mortality is the mountain pine beetle (MPB).
Mistletoe is a holiday tradition. We decorate our doorways with it, where tarrying under a spring might bring you a kiss. Unfortunately, the kind of mistletoe growing along Colorado’s Front Range isn’t so romantic. Five different species of dwarf mistletoe infest pines, spruces and firs. Given enough time, an infected tree will eventually die.
All mistletoes are flowering plants that have given up a life of self-sufficiency to become harmful parasites. Dwarf mistletoes lack leaves, so they have little ability to make their own food from sunlight. Instead of extending their roots into the soil, they have root-like structures that penetrate under the bark, where they siphon off both water and nutrients from the host tree.
The female mistletoe plant produces sticky seeds. When the seed capsules are ripe, usually in late summer, they explode, expelling their contents at speeds up to 60 mph! The seeds can travel up to 60 feet, although 30 feet is more common. Wherever the seeds hit, there they stick.