WHITE PLAINS, N.Y. (CBSNewYork) — The long, cold winter has been keeping pollen — and allergy symptoms — at bay.

Some trees should have started pollinating weeks ago. But Dr. Leonard Bielory with Rutgers University’s Robert Wood Johnson Medical School says to get ready for a one-two punch, as trees play catch-up.

“Late release, overlapping, and therefore much more intense, to the point where you may even see clouds of pollen being released over the next several weeks where there will be an almost yellow-green mist,” Bielory told WCBS 880’s Sean Adams.

“Elm, cedar and maple’s what we’re seeing now,” he added. “Then you’re going to see oak and birch be into the thousands, and they’re going to overlap in the last weeks of April. And with that, we’ll also start seeing the grasses.”

Bielory’s advice: See your allergist before symptoms start.

“There is also now over-the-counter steroid medications that are now approved,” he said. “… If you know you’re allergic to trees, my advice to you is start now.”

This year bucks a trend that Bielory, who has been studying climate change, has seen. In recent years, his counts show pollen release starting earlier and lasting longer.