These winds are getting to me, and I don’t even live on Florida Mesa.
They pick up in the afternoon, grabbing dust, dirt and pollen, and deposit them directly into my eyes and nose. I am a horticulturist with seasonal allergies (oh, the irony). By bedtime, my eyes are itchy, nose is running, and Beth knows she’s in for a night of snoring. Sorry.
Our plants don’t really like the winds, either. Our conifers and evergreens, battered by the cold, winter winds, show browning, reduced growth and even death of branches. Drive around Durango and you can find rows of arborvitae that were used as a windbreak or screen (again with the irony) with their north-facing branches dead or dying.
We typically diagnosis this as winter burn. Winter burn can be common when evergreens (which don’t shed their leaves or needles in winter) with broad leaves (boxwood and holly), needles (fir, pine, spruce) or scale-like leaves (arborvitae and junipers) are grown in spaces without some sort of protection and are exposed to harsh conditions for an extended period of time.
Typical symptoms start to show themselves when spring temperatures rise. The needles start to turn brown on the tips and then that progresses inward. The challenge is that diagnosing diseases or disorders in conifers can be really tough. So winter damage could be somewhat similar to beetle damage in our pines; seasonal shedding of needles, especially from the interior of the tree, can resemble water or drought stress; and to the naked eye, fungal pathogens can be confused with insect damage and only experts, like arborists, can really diagnose the causal agent or the reason why.
If you want to try to avoid winter damage to your conifer trees and shrubs, I do have some recommendations:
Use the mantra of Colorado Master Gardeners: right plant, right place. Don’t plant sensitive plants, such as boxwood or arborvitae, in spaces that aren’t protected. If you live in a location that gets consistent wind, especially in winter, reduce your expectations for success of conifers. Know which way the wind blows (remember: you don’t need a weatherman to know which way the wind blows) across your location, especially in winter. Plant conifers and evergreens during the spring. Optimally, you want to provide the trees enough time to develop a better root system in the plant’s new location. Conifers continue to transpire (lose water) in the winter, so their root systems still need to be taking up water. A more robust root system equates to greater potential for water absorption. Don’t prune in late summer or fall. Pruning induces new growth and new growth is much more sensitive. Water during the winter. While not always necessary, winter watering, especially for our conifers and evergreens, can be critical. However, it’s important to know you should only water when daytime temperatures are above 40 degrees, the ground isn’t frozen and is snow-free. Water only during midday so it will have enough time to soak in before freezing temperatures set in. I would recommend just using a soft spray from a wand attached to hose, applying the water at a slow rate to the dripline of the tree. As a general rule, apply 10 gallons of water once a month for each diameter inch of the tree.Darrin Parmenter is the director and horticulture agent of the La Plata County Extension Office. Reach him at [email protected]plata.co.us or 382-6464.Darrin Parmenter