Plants that produce pollen that’s spread in the wind (as opposed to by animals) are among the most common causes of hayfever (along with dust mites and pet dander from cats and dogs).
For Australians, that tends to mean grass pollen. If you live in the southern part of the country, ryegrass is a common cause of allergic rhinitis. The perennial grass is often planted in agricultural projects, but it’s also found in lawns and by roadsides. Its peak period of pollen production occurs in late-November, a time when allergy complaints tend to increase.
If you live in the north of Australia, watch out for subtropical grass species like bahia and bermuda grass which have been linked with allergic reactions. Pollen activity in these areas is high in October and November, and peaks again in the height of summer – due to late-blooming grasses.