June marks the start of what many here in the Northeast believe is the sweetest part of summer — berry season. It’s a time ripe with strawberry festivals, pick-your-own-berries and local farmers’ markets.  For berry lovers and local farmers, the season is much too short — usually about one month of strawberry harvest and another for fresh, local raspberries — a span of time researchers at Penn State’s College of Agricultural Sciences are working to extend.  See more here.