Predominant Pollen and Spores

Charlottetown, Prince Edward Island

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 Charlottetown, Prince Edward Island

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 vary from year to year due to weather. In warm years like 201 and 2012 the season can start close to mid-May. Generally the season starts from the first to the second week of April and ends the first to the third week of June. The counts can fluctuate from low to high throughout the season. They are considered important allergens.

Ash (Fraxinus sp.)

Ash season can generate mostly low and the occasional moderate counts. The season can start from mid-April to early May and end late May to the second week of June. At these levels they may cause allergic reactions only in highly sensitized individuals.

Beech (Fagus sp.)

Beech season can vary a great deal from year to year due to cyclical patterns and the effect of weather. Some years only low counts are observed but moderate counts are possible in certain years. The season can start from early to late May and end the third week of May to the first week of June.

Birch (Betula sp.)

There are two distinct seasons for birch. The first one lasts less than one week and can occur the last two weeks of April. The main season can start late April to the second week of May and end from the first to the third week of June. Most years high counts are observed. The season can be affected by weather. They are considered important allergens.

Cedars, Junipers and Yew (Cupressaceae family)

There is an early sporadic season for cedars, junipers, and yews with only low counts possible from mid to late March. The main season can start late March to the third week of April and ends late May to mid-June. The amount of pollen released varies from year to year. Some years only produce low counts whereas other years moderate and high counts are observed. They may not play an important role in allergic reactions.

Compositae family

The composite family, for which many are flowering plants, produce sporadic counts from August to the end of September. Some are considered important in causing allergic reactions.

Dock weed & Sheep sorrel weed (Rumex sp.)

Dock weed & sheep sorrel weed are important allergens. High counts are observed. The season can start from the third week of May to the second week of June and end early to late August. The most significant counts can occur in June to early July.

Goldenrod (Solidago sp.)

Goldenrod is a flowering plant, which produces sticky pollen and is mostly insect pollinated. The plant, however, is abundant at this collection site and sometimes significant number of pollen grains are captured on our samples. Mostly low, with an occasional moderate, counts are observed. The season can start from late July to early August and end mid-September to early October.

Grasses (Gramineae family)

Grass season starts mid to late May and ends late September to mid-October. Very high counts are observed in the months of June and July.

Hemlock (Tsuga sp.)

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

Maple (Acer sp.)

Maple season can have a very short early season, with low counts, from late March to mid-April. The main season, which lasts well over a month, can start from mid to late April and end the third week of March to early June.

The amount of pollen observed can vary from year to year. Some years only low and the occasional moderate counts are observed. Other years some high counts can be observed.

Nettles (Urticaceae sp.)

The counts for the 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 late August.

Oak (Quercus sp.)

Oak season can vary from year to year and is highly effected by weather. Generally only low counts are observed. Occasional moderate counts are observed during certain years. The season can start from the first to the third week of May and end late May to the third week of June. Certain species can cause allergic reactions.

Pine, fir and spruce (Pinaceae family)

Very high counts of pine, spruce and firs are observed and the season can start from the second to last week of May and end from the early to mid-July. Significant allergens for individuals who are sensitized.

Plantains (Plantago sp.)

Plantain season can start from the first to the third week of June and end mid to late September. Mostly low, with the occasional moderate, counts are observed. Even low counts can cause allergic reactions in highly sensitized individuals.

Poplar, cottonwood and aspen (Populus sp.)

Poplar and aspen season can last well over a month. There is a short early season with only low counts that may occur from the third week of March to the second week of April. The main season can start the first to the third week of April and end the first week to the end of may. The amount of pollen observed from year to year can vary and some seasons high counts are observed. May cause allergic reactions in individuals who are highly sensitized.

Ragweed (Ambrosia sp.)

Low counts of ragweed are observed for the ragweed at this location. The season can start from late July to mid-August and end late September to mid-October.

Willow (Salix sp.)

Willow season can be sporadic. Low and moderate counts can be observed. The season starts from the third week of April to early May and ends late May to mid-June. May only cause allergic reactions in highly sensitized individuals.

Predominant Spores for Charlottetown, Prince Edward Island

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.

Moderate to high counts of alternaria are observed from mid-June to mid-October. Some species are known to cause allergic reactions.

Aspergillus sp.

High counts of aspergillus are observed from mid-March until fall. They are considered important allergens.

Boletus sp.

Boletus is a type of mushroom where significant number of spores are observed from mid-June to mid-October. Considered an important allergen.

Caloplaca sp.

Caloplaca is sporadic throughout the counting season with some high counts from May to mid-October. Medical significance is unknown.

Cladosporium sp.

Cladosporium is one of the spores that can be found all year round. The relevant counts start in late March and the highest counts are seen from late May until fall.

Coprinus sp.

Significant counts of coprinus are observed from mid-May to mid-October. Considered to be a significant allergen.

Diatrypaceae sp.

Very sporadic counts diatrypaceae are observed from late March to late fall. Clinical significance is unknown.

Drechslera

Drechslera counts are never very high. This is mostly a summer and fall spore. There are other related genera, which are also found in air samples, that can cause respiratory problems. One example is Bipolaris sp.

Epicoccum sp.

July to mid-October is when the highest counts of epicoccum are seen in our samples. The counts may reach high enough numbers to be of clinical significance.

Erysiphe (Oospora) sp.

Erysiphe, also known as powdery mildew, sees moderate to high counts observed from April to mid-October. Clinical significance is not known.

Fusarium sp.

Fusarium counts fluctuate throughout the season which is normal for this fungus. The majority of the season is from May to late fall. A significant allergen.

Ganoderma sp.

Ganoderma spore is by far the most prevalent for total spores during the whole counting season. This is unusual since normally Cladosporium has the highest total count for the season in any location, so the abundance of Ganoderma is unique to this site. Considered to play an important role in allergic reactions and asthma. Very high counts are observed from June to late October.

Helicomyces sp.

Very high counts of helicomyces are observed throughout our counting season. Counts are very sporadic which is due to the effect of weather and the number of species present. Highest counts occur from June to mid-October.

Leptosphaeria sp.

Sporadic counts of leptosphaeria are observed from late April to late fall. Very high counts are observed and they could be of medical significance.

Myxomycetes

Sporadic counts of myxomycetes are observed from late March to the end of September. Mostly in the moderate range.

Penicillium sp.

High counts of penicillium are observed from mid-March until fall. They are considered important allergens.

Polythrincium sp.

Moderate counts of polythrincium are observed from mid-June to mid-October. Medical significance is unknown.

Uredinales sp.

Uredinales also know as rusts are found in high numbers from June to late fall.

Ustilaginales sp.

Ustilaginales or smuts are found in high numbers from late May to late fall.

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