The Marionberry is a blackberry developed by the The United States Department of Agriculture (USDA) breeding program in cooperation with Oregon State University in 1945. While the common blackberry is a species that has been around for thousands of years, the Marionberry is not a genetically modified organism (GMO). Instead, it is known as a recent hybrid of the 'Chehalem' berry and the 'Olallie' berry. Although Marionberries are often described as the "king of the blackberries," they’re still exclusively grown in Oregon.

The Marionberry has a more elongated shape and is larger in size than the common blackberry, or 'Alleghany blackberry'. These berries are often described as having a complex, rich and earthy flavor that is both sweet and tart. Compared to the common blackberry, Marionberries also have a firmer texture, which allows them to ship better.

The state of Oregon produces approximately 33 million pounds annually, with Marion County and the Willamette Valley collectively accounting for over 90% of current production. The harvesting season is between July and August; a single acre can produce up to six tons in a harvest.

The Marionberries that Oregon produces each year make it the most common blackberry in the state and it accounts for more than half of Oregon's entire blackberry crop. The common blackberry, however, continues to grow both naturally and on commercial farms around the world.

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