Gardening Corner: Spring brings the promise of ... allergies

Lewis Ziska, Associate Professor of Environmental Health Sciences at Columbia University states several reasons that relate to the extended season.

As the climate changes, spring changes are starting earlier. Second, the overall pollen season is primarily driven by tree pollens in the spring, weeds and grasses in the summer and the ragweeds in the fall. The studies show that the allergy season is 20 days longer in North America now than it was in 1990. As you move towards the poles, where temperatures are rising faster, the studies found that the season is becoming even more pronounced.

I think many of us who have lived in Central Oregon for an extended time, given a moment to reflect, can agree that we seem to have warmer temperatures these past few years. Remember the snows on 4th of July or the one day of the year the temperature hit 90 degrees?

A friend recently shared she was suffering the miseries of a migraine headache and lamenting it was a reminder that allergy season is just around the corner.

That is when I decided it was time to pull “The Allergy-Fighting Garden” by Thomas Leo Ogren from the bookshelf. Ogren is a horticulturist and allergy researcher, a former landscape gardening instructor and a nursery owner.

As gardeners who suffer from pollen allergies, we often look to landscape choices that are low-maintenance and litter-free when in reality we are actually planting the worst selections. The book offers explanations to better understand plant sex that will enable us to make better decisions in creating an allergy-free landscape.

The book is a guide providing an allergy rating scale for over 3,000 plants. The rating scale developed by Ogren is OPALS, an acronym for Ogren Plant Allergy Scale. The ratings are numbered 1-10, with 1 being the least allergenic and a ranking of 10 being the most allergenic. More than 130 possible factors are used to develop the ranking system, both positive and negative.

How can we use the information beyond our own backyard? According to the American Lung Association there has been an increase in juvenile asthma. Ogren writes of his visits to several elementary school sites in different states at the request of parents to evaluate playgrounds.

At one school he found twenty-one out of twenty-six trees were highly allergenic. At another school he found fifteen out of seventeen trees were highly allergenic. With new schools being planned in central Oregon, perhaps attention should be paid to the landscape plans to avoid creating or exacerbating existing health issues.

I found the entry on Pinus, (pines) in general to being very helpful. “Pines shed enormous quantities of pollen, but because the pollen grains are waxy and not highly irritating to mucous membranes, their potential for allergy is rather low and when it occurs, not usually severe. Allergic reactions to the scent of cut pine are reported but are also rare. There is one exception and that is P. contorta, the lodgepole pine is known to cause asthma and has an OPALS rating of 8.”

The book combines the best of Ogren’s previous books—Allergy-Free Gardening and Safe Sex in the Garden.

Special news department. The Central Oregon Master Gardeners Spring Gardening Seminar has a new twist this year. The 5 classes will be virtual classes offered between April 3 and April 24. Information on classes and dates is available at gocomga.com.