|Our 2-year remodel is nearly done; now we turn out attention to landscaping our 1/2 acre located in Zone 14-15. Mom and Dad suffer respiratory allergies (primarily seasonal pollens), kids too, and kids additionally suffer frommild chronic asthma from seasonal pollens and molds. I am trying to make smart choices for large landscape trees, smaller specimen trees, shrubs, etc. Blossoms and scent don't bother us. Problem seems to be limited to pollen. Read about the OPALS system of rating trees for pollen, and the issue of male trees vs. female trees, and wind-born pollen. Any recommendations for me? Designer has suggested two large Shamel Ash trees to anchor front corners of property at street - I hear they have extremely invasive roots, and males are polleny... City code requires that we select two 24-inch box evergreens for this spot. Any and all advice will be appreciated - re allergies, pollen, or the ash question.|
|One of the very biggest problems of all for allergy sufferers is that most communities have planted all male trees in the interest of avoiding litter and debris that female trees produce, such as seeds, pods, etc. Unfortunately, male trees produce pollen and without female trees to trap that pollen, you have airborne pollen flying around without a place to go except up your nose! So if you have seedless, fruitless trees in your yard or garden, chances are you have male trees. Female trees produce NO pollen and, therefore, are your safest bets for allergy-free gardening. Female plants and trees receive the pollen grains and act like traps or air scrubbers.
With this in mind, some of the worst offenders are male versions of ash, poplar (especially Italian and Lombardy poplars), willow, cedar, juniper, cottonwood, mulberry, box elder, holly, yew, pussy willow, Chinese gingko, smoke tree, seedless honey locust, and berry-less junipers.
Trees and shrubs rated best, and those you should try in your own landscape, include dogwood, crabapple, cherry, redbud, magnolia, and female versions of yew, juniper (Bar Harbor, blue point, and Iowa), yew pine, poplar, box elder, some maples (especially female silver and red maples such as Autumn Glory, and October Glory), willow, sour gum, azalea, fir, peach, plum, pear, and ash. Any holly with red berries is also a good choice.
The best choices in flowers are daffodil, iris, hollyhock, impatiens, nasturtium, pansy, begonia, crocus, poppy, tulip, clematis, peony, zinnia, and fully double sunflowers and chrysanthemums. Other herbaceous plants with showy flowers that are OK include daisies, geraniums, petunias, and roses. Perfectly flowered plants don?t cause problems because their pollen is heavy and sticky and is transferred by insects not the air.
Hope this information is helpful!