Ragweed
Mugwort
Birch
Hazel
Ash
Grass
Plantain
Oak
Main allergenic pollens
All pollens do not provoke allergies. To cause allergy symptoms, it is essential that the pollen grains arrive to the respiratory mucosa of human being. Only plants anemophilous disseminate pollen grains by the wind, while entomophilous plants require the intervention of an insect to ensure fertilization by transferring pollen from the male to female flower receiver.
The pollens of high allergenicity are produced by anemophilous plants (trees and grasses).
To be allergenic, pollen grain must contain substances (proteins or glycoproteins) immunologically recognized as harmful to an individual.
The allergy potency of a plant species is the ability of its pollen to provoke an allergy for a part of the population.
Allergy potency can be:
- weak or null (species which can be planted in urban areas)
- Moderate (only a few trees or herbaceous of these species can be planted in urban areas)
- Strong (species which can not be planted in urban areas)
Comparative table of the different plants according to there allergy potency
| Trees | ||
| Species | Family | Allergy potency |
| Maple* | Aceraceae | Moderate |
| Alder* | Betulaceae | High |
| Birch* | High | |
| Hornbeam* | High | |
| Hop-Hornbeam | Low/Null | |
| Hazel* | High | |
| Eastern Baccharis | Composate | Moderate |
| Cade | Cupressaceae | High |
| Mediterranean Cypress | High | |
| Arizona Cypress | High | |
| Juniper | Low/Null | |
| Whitecedar* | Low/Null | |
| False Acacia* | Fabaceae | Low/Null |
| Chestnut* | Fagaceae | Low/Null |
| Beech* | Moerate | |
| Oak* | Moderate | |
| Walnut* | Juglandaceae | Low/Null |
| Paper Mulberry* | Moraceae | High |
| White Mulberry* | Low/Null | |
| Ash* | Oleaceae | High |
| Olive | High | |
| Privet* | Moderate | |
| Pine* | Pinaceae | Low/Null |
| Plane** | Platanaceae | Moderate** |
| Poplar* | Salicaceae | Low/Null |
| Willow* | Moderate | |
| Yew* | Taxaceae | Low/Null |
| Japanese Red Cedar | Taxodiaceae | High |
| Lime* | Tilliaceae | Moderate |
| Elm* | Ulmaceae | Low/Null |
|
*several species |
||
| Spontaneous Herbaceous | ||
| Species | Family | Allergy potency |
| Gosefoot* | Chenopodiaceae | Moderate |
| Saltwort (Salsola kali) |
Moderate | |
| Ragweed* | Composate | High |
| Mugwort* | High | |
| Oxeye daisy* | Low/Null | |
| Dandelion* | Low/Null | |
| Mercuries* | Euphorbiaceae | Moderate |
| Plantain* | Plantaginaceae | Moderate |
| Grasse | Poaceae | high |
| Sorrel* (Rumex) | Polygonaceae | Moderate |
| Nettle* | Urticaceae | Low/Null |
| Pellitory | High | |
| *several species | ||
| Ornamental Grasses | ||
| Species | Family | Allergy potency |
| Reed canary grass | Poaceae | High |
| Reed grass | Moderate | |
| Tufted hairgrass | High | |
| Sand Ryegrass | Moderate | |
| Fescue* | High | |
| Oatgrass | High | |
| Hare's tail | Moderate | |
| Giant feather grass | Moderate | |
| *several species | ||
Recognize treesand grasses with allergenic pollens
You can download by clicking on the links below posters that will allow you to recognize the trees and grasses emitting allergenic pollen (in French), with an indication of the allergy potency related to the pollens.