Predominant Pollen and Spores
Sherbrooke, 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 Sherbrooke, Québec
The 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 season can start mid-March to early April and end early to late June. Moderate and high counts can occur. Alders are considered important allergens.
Ash (Fraxinus sp.)
Ash season can start from mid-April to early May and end mid-May to early June. Some very high counts can be observed and this could cause allergic reactions in sensitized individuals.
Beech (Fagus sp.)
Beech season varies a great deal from year to year. This is partly due to cyclical patterns and weather. The season can start from early to mid-May and end late May to the second week of June. Most of the counts are low but in rare years moderate counts are observed.
Birch (Betula sp.)
Birch season can start from mid-April to early May and end early to late June. Very high counts are observed and they are considered important allergens.
Cedars, Junipers and Yew (Cupressaceae family)
Cedars, junipers and yews season starts from early to late March and ends late May to early June. Very high counts can be observed but most species in Canada are not considered allergenic.
Elm (Ulmus sp.)
Elm are highly allergenic. An early sporadic season, with low counts, can ocur the third week of May to early April. The main season, which usually has moderate counts, can start the second to third week of April and end late April to early May.
Grasses (Gramineae family)
Grasses season can start early to mid-May and end early October. Moderate and the occasional high counts are observed from early June to late July.
Hemlock (Tsuga sp.)
Hemlock season lasts approximately one to three weeks and varies a great deal from year to year. The season can start from the second week of May to early June and end the third week of May to the second week of June. Some years moderate and high counts are possible.
Hop Hornbeam (Ostrya sp.) & Hornbeam (Carpinus sp.)
Low to moderate counts are possible for Hop Hornbeam & Hornbeam. The season can start late April to early May and ends late May. Some species can cause allergic reactions.
Larch (Larix sp.)
Larch season can vary a great deal from year to year. The season can produce moderate counts or very sporadic low counts. The season can start mid to late April and end late April to early May.
Maple (Acer sp.)
Maple can have a short early season from mid to early April. The main season can start from early to mid-April and end mid to late May. Some very high counts are observed and some species are known to cause allergic reactions.
Nettles (Urticaceae sp.)
Nettles and the parietaria produce low and moderate counts. The season can start mid to late June and end mid to late September. They are considered important allergens due to their small size.
Oak (Quercus sp.)
Oak season can start from mid-April to early May and end the third week of May to early June. The counts can get high and some species are known to cause allergic reactions.
Pine, fir and spruce (Pinaceae family)
High counts are observed throughout the season for pine, fir and spruce. The pollen season can start from late April to the second week of May and ends early to late July. This group of trees are important to those individuals sensitized.
Plantains (Plantago sp.)
Plantains produce mostly low and occasional moderate counts. The season can start late May to early June and late September. They can cause allergic reactions even in low numbers to sensitized individuals.
Poplar, cottonwood and aspen (Populus sp.)
Poplar, cottonwood and aspen produce very high counts which can cause allergic reactions. The season can start from the third week of March to the third week of April and end early to mid-May. The season can start early in warm years like 2010 and 2012.
Ragweed (Ambrosia sp.)
Ragweed season can begin from mid-July to early August and end early to mid-October or with a heavy frost. Moderate counts can be observed from the second week of August to early September.
Sagebrush (Artemisia sp.)
The main sagebrush and wormwoods produce mostly low and the occasional moderate count from the second week of July to early October. May be a source of allergenicity.
Willow (Salix sp.)
The season for willows season lasts about four weeks. The season can start mid to late April and end mid to late May. Occasional moderate counts are possible which may cause allergic reactions in sensitized individuals.
Predominant Spores for Sherbrooke, 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 forAlternaria are found from June to mid-October and are generally in the low to high ranges. May not cause allergic reaction except in highly sensitized individuals.
Aspergillus sp.
Significant counts for Aspergillus occur throughout the whole counting season with high counts occurring from March to late fall.
Boletus sp.
Boletus season is from June to the end of October. Late July to October is when the highest counts are observed.
Botrytis sp.
Counts for Botrytis are in the low to moderate ranges from April to early October.
Caloplaca sp.
Moderate and high counts are observed from mid-May to late September. Season is very sporadic. May not be an important cause in allergic reactions.
Cladosporium sp.
Cladosporium are found throughout the whole counting season. High counts are observed in March and April with very high counts starting June to late fall.
Coprinus sp.
High counts of Coprinus are observed with the season running from May to late fall. May be an important allergen.
Diatrypaceae sp.
Counts for are Diatrypaceae 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 to high counts of epicoccum occur from June to mid-October.
Erysiphe (Oospora) sp.
Erysiphe aka Powdery mildew season starts mid-April until mid-October. Counts are in the low to very high ranges. May not be an important allergen
Fusarium sp.
Sporadic counts of Fusarium are observed throughout the whole collecting season. Moderate to high counts are observed from May to early October.
Ganoderma sp.
Very high counts of Ganoderma are observed from June to mid-October. May be an important allergen.
Helicomyces sp.
The season for Helicomyces is very sporadic and low to high counts are observed from April to mid-October.
Helicomyces sp.
Leptosphaeria is found in air samples, food, soil and plant material. The season is from February to mid-October. The counts vary from day to day, which is probably due to the effect of weather. Low to high counts are observed. They can cause allergic reactions, asthma attacks and skin infections.
Myxomycetes
Low and moderate counts are observed from May to mid-October.
Penicillium sp.
Significant counts of Penicillium occur throughout the whole counting season with high counts occurring from March to late fall.
Pithomyces sp.
Low to moderate counts of Pithomyces are observed from June to early October.
Polythrincium sp.
Very high counts are observed from June to the end of September.
Uredinales sp.
Uredinales commonly named Smuts produce low to high counts from May to mid-October. Allergenicity is unknown.
Ustilaginales sp.
Ustilaginales also commonly referred to as Rusts produce low to high counts from May to mid-October. Allergenic properties are not well understood.
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