As the sneezing starts, a call for better trees in Canberra

But for Eloise Robertson, the new season means fear.

She suffers attacks of asthma which are so severe that she ends up in hospital. One year, she was taken there 12 times as pollen acted on her lungs and choked her airways.

Sometimes, she is taken in as an emergency case. Sometimes it lasts for a week.

So she avoids newly mown grass. Wattle frightens her. If her friends go out, she checks the pollen count and sometimes stays in. Her home is full of air purifiers and inhalers.

"Canberra has a reputation for being bad for asthma, and that's not a good reputation to have," the 22-year-old student says.

As the city's sufferers start sneezing and wheezing in another season of pollen clouds, new figures show one in three Canberrans are sufferers from hay fever.

According to Simon Haberle, a Professor of Natural History at the Australian National University, 10 years ago that number was only one in five.

Hay fever causes sneezing and watering eyes. With asthma, the airways get constricted so it's harder to breathe. Both are often an allergic reaction to substances in the air, particularly pollen from trees and grasses.

Professor Haberle wants the ACT government to think harder about what kind of trees it's planting.

There is an economic cost to hay fever and asthma, he feels, in that they slow people down at work or even force them to take time off.

Now is the season, lasting through to March, as new types of trees and grass produce pollen at different times.

"There should be more attention to the planting of trees that don't cause hay fever," the pollen expert says (and Ms Robertson agrees wholeheartedly).

Professor Haberle says cypress pines have already started producing pollen, followed by elms about now, and soon, birch and plane trees. November is the peak month for grass.

And then some of the trees get a second go in February.

The fact that the ACT is the worst part of Australia for asthma and hay fever is partly because it's landlocked, and nothing can be done about that. In other cities, the sea breeze disperses the pollen to lessen its impact on lungs and airways.

But Canberra's situation also comes down to the vigorous tree planting which has been taking place as the city has grown.

"Part of the reason Canberra is such a hot spot is because it's landlocked but it's also been beautifully landscaped, and newly planted trees have allergens (substances to which people are allergic)," Professor Haberle says.

He thinks more attention needed to be paid to measuring the effects of the increased foliage in the city. Pollen and its effects need to be quantified as the season progresses, he says.

The ACT's acting Chief Health Officer, Dr Kerryn Coleman, agrees asthma and hay fever are significant health problems in Canberra.

She recommends a new app for smartphones which provides "real-time information on pollen and air quality".

The AirRater app aims to help keep people informed about risks from air quality.

"I encourage people to download it as a preventable measure for themselves and their loved ones, whose symptoms may be triggered during Spring," Dr Coleman says.

She says the government has also improved its own advice website. There is also immediate information available on the Canberra Pollen Count and Forecast Service.