Interior Alaska’s hot and dry summer of 2013, coupled with an invasion of insect pests, has taken a steep toll on the region’s birch trees, experts say.

A terrible year for berry harvest in the Upper Nushagak River.

A great year for harvesting mossberries.

Crooked Island, 25 Miles south of Togiak. Remnants of blackberries.

08-17-14 Abundant bees - Eagle River, Alaska, USA

Abundance of Fireweed on Popof Island

7-14-14 Yellow flowers genus Arnica - Togiak, Alaska, USA

7-14-14 Abundant bees & berries - King Cove, Alaska, USA

Early blueberries in Jakolof Bay, Alaska

In just seven years, as much as one-third of the mountain-birch forest in the North Calotte region was severely defoliated by two moth species. Researchers now have a better understanding of what happened.

5-27-14 Early salmon berry blossoms - Toksook Bay, Alaska, USA

5-25-14 High spruce pollen McDonald Spit, Alaska, USA

5-19-14 Poor air quality - Anchorage Alaska, USA

1-24-14 Winter plants blooming - Bethel, Alaska, USA