Sneezing time

ragweed THIS IS A MISERABLE TIME of year for many allergy sufferers. Unfortunately, people with allergies often blame the wrong plants, which does nothing to relieve their suffering and may prevent them or even their neighbors from planting harmless species.

Left, the pollen of Common ragweed causes most respiratory allergies at this time of year. This photo is by Forest and Kim Starr, via the Wikipedia Commons.

As it happens, a wildlife-friendly garden is likely to be an allergy-sufferer's best friend. Why? Because plants that are pollinated by insects tend to have heavy pollen. Because it’s heavy, this pollen is not carried on the wind, which means that it does not have a chance to get into your nose and start the immune-system reaction known as an allergy attack. So a wildlife-friendly garden full of flowers that are being visited by butterflies, bees, and other pollinators is not likely to cause allergic reactions.

In late summer, the chief cause of respiratory allergy symptoms is ragweed (Ambrosia artemisiifolia). This is an annual weed that’s common in the Northeast, Midwest, and South. Although it’s native to North America, I’ve never heard anyone recommend it as a garden plant!

Ragweed pollen can travel hundreds of miles but most of it lands near the plant, so the closer the plant is to you the more likely it is that the pollen will end up in your nose. If there is any ragweed growing near you, the best way to dispose of it is probably to wet it down (to make the pollen grains heavy, so they don’t scatter), then cut it back carefully and again carefully put the stems into a plastic garbage bag, which can be put out with the trash. The best time to do this would be early on a chilly morning, when pollen production would be at its lowest.

For future years, the best way to keep ragweed off your property is to plant aggressive perennials, preferably ones that are pollinated by insects, because these plants can prevent the annual ragweed from getting a foothold in your garden. In other words, have a wildlife-friendly garden! Goldenrod might be a good choice because it is insect pollinated and extremely aggressive.

One warning: People who are allergic to ragweed pollen may also be allergic to the pollen of other plants in the Aster family. Now, the Aster family is huge and includes many wonderful wildlife-friendly plants with heavy pollen, including Goldenrod and Purple coneflower. It would be a tragedy for any wildlife-friendly gardener to give up these plants altogether. But if you are allergic to ragweed, you may want to plant these species further from your house and avoid bringing the flowers into your house or working right next to them during pollen season. Sniffing the flowers of plants in the Aster family would also be ill-advised, as that would pull even heavy pollen into your nose.

Meanwhile, here are a few ways to keep allergies under control this time of year. Most of them come from the American Academy of Allergy Asthma and Immunology.

  • Try to stay inside with the windows closed when pollen counts are high. This is generally between 10 am and 4 pm on dry days. (Rainy days are safer because the rain washes the pollen out of the air.) You can get local pollen counts from the National Allergy Bureau at (800)-9-POLLEN, or
  • An air conditioner helps because it cools and dries the air, an HEPA filter can clean the pollen out of the air.
  • And of course you need to avoid anything that would stir up pollen or bring pollen into your house during pollen season, from raking leaves to hanging clothes outside to dry (because pollen collects on the clothes). If you've been working outside, change your clothes when you come inside.
  • If you do go outside when pollen counts are high, you could try wearing a pollen mask.
  • Another tip is to keep your bedroom closed up during the day and then bathe before you go to bed. This will prevent pollen from getting into your bedding.
  • Also, I'm sure any allergy sufferer who is willing to take drugs has already tried all the over-the-counter drugs, but have you tried nasal rinsing? This will wash pollen grains out of your sinus cavities. Here are instructions from the AAAAI.


Town Mouse said...

During allergy season, I have a shower, wash my hair, and put away any "outside" clothes after I've been outside. Washing the hair seems to really help.

I've had bad luck with the HEPA filter thing, the big ones are noisy and smell funny, it actually made breathing harder for me.

Wild Flora said...

Hi Town Mouse,
I'm sorry to hear that you suffer from allergies, but it certainly sounds as though you have a good system for keeping them under control. I'm very lucky--I don't seem to be allergic to anything except nickle (and that's my own fault-- coming from having had my ears pierced). But I've had to learn about allergies because they often come up in discussions of "wild" landscaping. My own husband, who does have spring allergies, objected to my first flower garden because he thought it would make his allergies worse. (Wrong!) And I have found that neighbors who are nervous about any type of landscaping that isn't lawn will often bring up allergies as one of many reasons they object. The irony in that is that people tend to be allergic to the things they're most exposed to, meaning that these days many people are allergic to pollen from lawn grass and ornamental trees, not native plants.

Sarah O. said...

Nova Scotia historically had very little ragweed (it started to increased after the 1930s, but even so I don't notice it much in HRM) and we used to advertise the province to allergy-suffering tourists as a place free from ragweed! It was part of our whole "healthful climate" pitch. Maybe we should start using that angle again?

Wild Flora said...

Interesting comment, Sarah O. Various reliable sources list common ragweed as native and present throughout mainland North America except for the far north, so it must have been present in this province since before Europeans arrived. Of course that doesn't tell us how common it used to be. Given that it spreads readily, however, and is almost impossible to control, I'd guess that it's probably pretty common in Nova Scotia now. Possibly you don't see much of it in HRM because people pull it? Unfortunately from what I've read, pulling it doesn't do much to prevent it from spreading, in fact can actually help to spread the seeds.

Anonymous said...

Went to a wildlife management workshop recently and learned ragweed
is a favorite of quail for food and cover. Another important thread in the complex web.

Wild Flora said...

Dear anonymous,

Thanks for making this point. Many plants that are commonly regarded as weeds are beneficial for wildlife. (Milkweed is another good example--essential for monarch butterflies, yet regarded as an agricultural pest.) It's generally safe to assume that any native plant plays a beneficial role in the environment as a whole, even if it causes problems for humans.