Predominant Pollen and Spores

Québec City, Québec

Tree pollen and spore seasons fluctuate from year to year by as much as two to four weeks at this site due to the effect of weather. The pollen and spore seasons described here are generalizations as to when pollination/sporulation occurs.

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Predominant Pollen for Québec City, Québec

Tree pollen seasons fluctuate from year to year by as much as two to four weeks at this site due to the effect of weather. The pollen seasons described here are generalizations as to when pollination occurs.

Alder (Alnus sp.)

Alder counts fluctuate throughout the season from year to year due to the number of species found and the effect of weather. A short early season, with low counts, may occur from the second to the last week of March. The main season can start from late March to mid-April and end early to late June. Some years high counts are observed. They are considered important allergens.

Ash (Fraxinus sp.)

Ash counts observed can be in the low to high range and will cause allergic reactions in those individuals who are highly sensitized. The season lasts well over a month. The season can start the third week of April to mid-May and end the third week of May to almost mid-June.tart from mid-April to the third week of April and end late May to early June.

Beech (Fagus sp.)

Beech season can start from early to late May and end late May to the second week of June. The seasons vary from year to year due to the effect of weather and normal cyclical patterns. Some years moderate counts are observed and other years only low sporadic ones are captured.

Birch (Betula sp.)

Very high birch counts are observed but the season dates and counts fluctuate from year to year due to the effect of weather. The season can start from late April to mid-May and end the first to third week of June. They are considered important allergens.

Cedars, Junipers and Yew (Cupressaceae family)

Cedars, junipers, and yews produce low to high counts. The season can start from early March to early April and end mid-May to early June. The species found in Canada are generally not considered allergenic.

Elm (Ulmus sp.)

Elm are considered important allergens. An early season can occur from mid-March to early April. The main season can start from early to late April and the season end is from early to late May. High counts are observed.

Grasses (Gramineae family)

Early low sporadic counts of grasses can occur in early May. The main grass season can start from the second to last week of May and ends early to mid-October. Moderate counts for the grasses occur from June to mid-July. The grasses are important allergens

Hemlock (Tsuga sp.)

Hemlock season can vary a great deal from year to year. This is due to the effect of weather and natural cyclical patterns. Some years sporadic only low counts are observed, whereas other years moderate and high counts are captured. The season starts from mid-May to early June and ends early to mid-June. May cause allergic reactions in individuals who are highly sensitized when shed in high numbers.

Larch and Tamarack (Larix sp.)

Larch and tamarack can vary a great deal from year to year due to the effect of weather and cyclical patterns. Some years only low and sporadic counts are observed while other years moderate counts are captured. The season can start from the third week of April to early May and end early to late May.

Maple and Box Elder (Acer sp.)

Maple has an early season that lasts approximately one week and can occur from late March to early April. The main season can start from the first to the last week of April and can end mid to early June. Moderate and high counts are observed. Certain species are important in causing allergic reactions.

Nettles (Urticaceae sp.)

Nettles and parietaria are considered important allergens due to their small size. Mostly low, with the occasional moderate, counts are observed. The season can start from late June to the first week of July and end late August to mid-September.

Oak (Quercus sp.)

Oak season can start from the first to the third week of May and end late May to early June. The season can be affected by weather. Most years high counts are produced and certain species are known to cause allergic reactions.

Pine, fir and spruce (Pinaceae family)

High counts of pine, fir and spruce are observed throughout the season. The pollen season can start from the first to third week of May and end late June to mid-July. The variation in when the season occurs is due to the effect of weather. This is a very important group of trees to individuals who are sensitized.

Plantains (Plantago sp.)

Plantain season can start the second week of June to early July and end late September to early October. Only low counts are observed. Can be a significant allergen even at low levels.

Poplar, cottonwood and aspen (Populus sp.)

Poplars, cottonwood and aspen produce high counts. The season can start from the third week of March to the second week of April and end early to late May. Allergic reactions may occur in highly sensitized individuals.

Ragweed (Ambrosia sp.)

Ragweed season can start from early to mid-July and ends well into October with a solid frost. Moderate and high counts are observed from early August to mid-September. They are considered to be a significant allergen.

Walnut (Juglans sp.)

Walnuts are considered important in causing allergic reactions. The pollen season can start from the second week of May to early June and can end early to late June. The season can vary a great deal from year to year due to weather and cyclical patterns. Low and sometimes sporadic counts will be observed whereas an occasional year can produce moderate and high counts.

Predominant Spores for Québec City, Québec

Spore seasons fluctuate from year to year by as much as two to four weeks at this site due to the effect of weather. Spores described here are generalizations as to when sporulation occurs.

Alternaria sp.

Most of the significant counts of alternaria are found from June to mid-October and are in the low to high range. May not cause disease except in highly sensitized individuals.

Aspergillus sp.

Significant counts of aspergillus occur throughout the whole counting season with the high counts occurring from March to late fall.

Boletus sp.

The main boletus season is from June to mid-October. Moderate and high counts are observed from July to mid-October. It is considered to be an important allergen.

Botrytis sp.

Botrytis counts are mostly in the low to moderate ranges from late May to early October.

Caloplaca sp.

Caloplaca season is very sporadic. Moderate counts are observed from July to mid-October. May not be a significant allergen.

Cladosporium sp.

Cladosporium is found throughout the whole counting season. High counts are observed late March to late fall. Some species are known to cause allergic reactions.

Coprinus sp.

Moderate and high counts of coprinus are observed and the season is from May to late fall. Considered significant in causing allergic reactions.

Diatrypaceae sp.

Diatrypaceae counts are very sporadic and vary throughout the whole counting season. Very high counts are observed from March to late October. They are not known to cause allergic reactions.

Epicoccum sp.

Low and moderate counts of epicoccum are observed from June to mid-October. Some species are known to cause allergic reactions.

Erysiphe (Oospora) sp.

Erysiphe, also known as powdery mildew, season is from the end of April to late October. The counts range from low to high. May not be an important allergen.

Fusarium sp.

Fusarium has a sporadic season with low to high counts observed from April to mid-October.

Ganoderma sp.

Moderate and very high counts of ganoderma are observed from late May to late fall. Considered significant in causing allergic reactions.

Helicomyces sp.

Helicomyces season is very sporadic with low to high counts observed from late April to the end of September.

Leptosphaeria sp.

Leptosphaeria season is from late April to mid-October with great fluctuations in counts from day to day which is due to the effect of weather and the number of species present. Some very high counts are observed for both groups. Can cause allergic reactions.

Myxomycetes

Low to moderate counts of myxomycetes are observed from late March to mid-October.

Penicillium sp.

Significant counts of penicillium occur throughout the whole counting season with the high counts occurring from March to late fall.

Pithomyces sp.

Moderate counts of pithomyces are observed from July to early October.

Polythrincium sp.

Low and moderate counts of polythrincium are observed from late June to mid-October.

Uredinales sp.

Uredinales also know as rusts produce low to moderate counts from late May to mid-October. Allergenic properties are not well understood.

Ustilaginales sp.

Ustilaginales or smuts produce low to high counts from late May to mid-October. Allergenic properties are not well understood.

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