Predominant Pollen and Spores

Alder season can start from the third week of March to mid-April and end mid to late June. Some high counts are possible but not all years. They are considered important allergens.

Ash season lasts approximately four weeks with low to high counts. The season can start from the third week of April to the second week of May and end the third week of May to mid-June. At these levels they would cause allergic reactions in sensitized individuals.

Beech season can vary a great deal from year to year due to cyclical patterns and the effect of weather. Low counts are generally observed but moderate counts are possible in certain years. The season can start late April to the third week of May and end late May to mid-June.

Birch season can start from the second to the last week of April and end early to late June. Some very high counts are observed and they are considered important allergens.

Cedars, junipers, and yews produce low to high counts lasting approximately four to five weeks. The season can start mid-March to early April and end mid-May to early June. High counts are observed. Most species in Canada are not considered allergenic.

Elms are an important allergen. The season can be sporadic which is mostly due to the effect of weather. Some years moderate counts are observed. The season can start late March to mid-April and end late April to the third week of May.

Grass season starts with low counts in May. The season with moderate counts is from mid-June to the third week of July. The season ends late September.

Hemlocks usually only produce low counts but rarely moderate counts can occur. The season varies a great deal from year to year due to the effect of weather and cyclical patterns. The season can start from mid-May to early June and end from the first to the third week of June.

Maple season starts late March to the third week of April and ends second to last week of May. Mostly low, with the occasional moderate, counts are observed. Certain species are known to cause allergic reactions.

Counts for nettles are always low but they are important allergens due to their small size. The season can start from mid-June to early July and end early to mid-September.

Oak season are effected by weather. The first season can start from late April to mid-May , whereas the more stable season can occur late April to mid-May. The season can end late May to mid-June. High counts are observed and some species can cause reactions.

Pine, spruce and fir season can start first to last week of May and ends the first to last week of July. Very high counts are observed. They are important allergens to people who are sensitized

Plantain counts are always low but even at these levels the plantains can cause allergic reactions in some individuals. The season starts from mid to late June and ends late September.

Poplar, cottonwood and aspen season with low to moderate and occasional high counts are observed. The season generally can start from the second to last week of April. During warm years like 2010 and 2012 the season can start as early as the last week of March to the first week of April. There is also a large variation as to when the season can end which is from the first to the last week of May.

Only low counts of ragweed are observed at this site and the season can start from mid-July to mid-August and last until late September to mid-October.

Only low counts are observed for willows generally. The season can start mid-April to early May and end late May to early July.

Most significant counts of alternaria are found from July to mid-October. Counts may not be high enough to cause allergic reactions except in highly sensitized individuals.

Significant counts of asperigillus occur throughout the whole counting season with the highest counts occurring late summer and fall.

Boletus season is from June to mid-October with moderate to high counts. May be considered allergenic.

Botrytis counts are mostly in the low to high ranges from June to early October.

Low to moderate counts are observed from April to early October. May not be of any significance in causing allergic reactions.

Cladosporium is found throughout the whole counting season. Low to moderate counts occur from March to June. The highest counts are observed from June to late fall.

High counts of coprinus are observed from June to late October. Considered to be a significant allergen.

Diatrypaceae spore counts are very sporadic and vary throughout the whole counting season. The highest counts are from the end of March to early October. They are not known to cause allergic reactions.

Mostly low counts of epicoccum are observed from June to mid-September. Some moderate counts are observed late September to mid-October. May not cause allergic reactions except in highly sensitized individuals.

Erysiphe, also known as powdery mildew, season is from mid-April to the end of September. High counts are observed. They may not be of importance in causing allergies.

Very high counts of ganoderma are observed from mid-June to late fall. Considered to be a significant allergen.

Helicomyces counts fluctuate throughout the season with moderate to high counts from May to October. Allergenic properties are unknown.

Leptosphaeria season runs from May to the end of September with great fluctuations in counts from day to day. This is probably due to the effect of weather. The significant counts, which are mostly in the moderate range, may cause allergic reactions in highly sensitized individuals.

Moderate counts of myxomycetes are observed from late April to mid-October.

Significant counts of penicillium occur throughout the whole counting season with the highest counts occurring late summer and fall.

Only low counts of pithomyces are observed from June to early October.

Low to moderate counts of polythrincium are observed from July to late September.

Uredinales also known as rusts produce low to moderate counts from late May to mid-October.

Ustilaginales or smuts produce low to high counts from June to late October.