Allergies can develop to many things, with allergies to plants being very common. As a general rule allergies to plants can be divided into two general categories. For simplicity when we refer to plants in this article, we are including trees, grasses, weeds and shrubs etc.

Inhaled allergies (traditionally referred to as “atopy”)
Inhaled allergens are those which can blow in the breeze for kilometres, such as plant pollens. As such, these cannot easily be avoided. Depending on the severity of the allergies and the region you inhabit (eg tropical, sub tropical, temperate) these types of allergies are commonly seasonal as different plants pollenate at different times of the year. Spring is certainly a bad time for many allergy sufferers as many plants pollenate at this time.
Allergies to inhaled allergens typically develop by 3 years of age in dogs, and are not commonly seen prior to 6 months of age. Therefore a very young or very old dog that develops a skin problem for the first time, is less likely to suffer from inhaled allergies or ‘atopy’.