If it seems like your seasonal allergies are getting worse and worse every year, you could be right - and you are not alone.  I suffer tremendously ever year, and it feels like te itchy and watery eyes, sneezing, running nose, etc feel like get more intense and uncomfortable year after year for me.  California horticulturist Thomas Leo Ogren thinks that it has everything with Botanical Sexism.

Botanical Sexism occurs when landscapers (both professional and amateur) pick predominately male dioecious plants for their projects.  Dioecious species of plants, like Red Mulberry and Ginko, are either male or female.  The female produces the eggs (and after fertilization - the seeds) and the male produces the pollen.  The males are picked for decorative purposes because they are cleaner.  Female dioecious specimens drop tons of seeds, pods and fruits for a potential homeowner to clean up.  Because of this, the males are overwhelmingly pick over the females when it comes to landscaping.  According to the Mother Nature Network, this overabundance of male plants pumping their pollen in the air (especially in residential areas) could be the reason you and I are sneezing more and more every year.

If you are looking to do a little work in the yard (or have it done), check with your local nursery to find a good mix of male and female plants, or consider monoecious species (both male and female) to fill out those flower beds.