The ponderosa pine is the culprit that has coated cars and outside surfaces with its gritty, yellow pollen.

But it’s not the pine pollen that’s causing people to itch and sneeze this month.

Dr. Kevin Kral, an allergist in Bend, said it’s grass pollen causing the sneezing, itchy eyes and runny noses during June. And the grass pollen isn’t from the newly mowed lawn, but the wild grass on the side of the road.

With allergy season in full swing, local allergists say that although juniper pollen has worsened this year, it has been an average allergy season.

Still, the grass pollen is causing grief for people suffering from seasonal allergies.

“The major amount of grass is the roadside grass that grows a couple feet tall,” said Kral, 57. “When you see the grass growing from green to yellow, that’s when the pollen is peaking. The drying out of (the grass) makes it easier to facilitate dispersion of the pollen.”

Kral said few people are allergic to pine pollen, although, like sawdust, it can be irritating if inhaled.

“So even though people see lots of pine pollen all over their cars, it’s really not a problem for the vast majority,” Kral said.

Dr. Joel Depper, an allergist in Bend, said he is still seeing patients who suffered from the juniper pollen earlier this year and do not want a repeat of their symptoms next season.

“The juniper this year was very bad. This was one of the worst in four to five years,” said Depper, 60. “But one thing you can depend on is the time frame of when the pollen pollenates.”

Although the weather has been cooler in the past few weeks, allergy season is on schedule with uncut wild grass being the main cause of allergies in June. For the majority of people suffering from severe allergies, the symptoms are winding down after the juniper season.

Juniper is the biggest contender for causing pollen allergies in Bend. Pollen allergy season begins with juniper in March and April, grass in June and July, and rabbitbrush and sagebrush in August and September.

Darlene Southworth, professor emeritus of biology at Southern Oregon University, has studied various aspects of pollen structure and development for 40 years.

Southworth said the flowering season this year is longer, causing plants like grass to grow larger.

“The increased rainfall has promoted a lot of flowering,” said Southworth, 66. “The plants haven’t dried out so quickly and have gotten very large.”

Southworth said grass pollen is much more allergenic than tree pollen because of the proteins being released.

When grass pollen becomes moist, the pollen’s proteins are released into the air, she said.

“The pollen that makes you sneeze are from the plants that don’t have beautiful flowers,” Southworth said.

So why are some people affected by pollen allergies and some are not?

“Allergies are very much a genetic process,” Depper said. “Fifteen percent of the population inherits the genes for allergies.”

Depper said the two main types of allergies are pollen and indoor allergies, such as from dogs and cats.

Generally, people will develop seasonal allergies by age 20, Depper said. However, juniper pollen can cause people to have allergies despite being allergy-free for years.

“The hardest thing to tell if you only have symptoms for a few days is it’s not that different than a bad cold,” Depper said. “You’re stuffed up and your nose is draining. With a cold, you’re more likely to feel achy.”

He suggested people with allergies keep windows closed, use some kind of air filtration inside and limit time spent outdoors.

Depper said he expects the allergy season will subside by the middle of October.

Allergies on a schedule

According to Dr. Joel Depper, a Bend allergist, when pollination occurs is consistent throughout the years. For example, juniper — Central Oregon’s worst allergy-inducing pollen — pollinate in March and April. Following are the peak allergy months of the plants that affect pollen allergies:

March/April: Juniper

May: Pine, bitterbrush

June/July: Uncut grass

August: Rabbitbrush, ragweed

September/October: Sagebrush