The san marzano is indeterminate in nature (it bears fruit over an extended period), with fruits grouped in bunches of five or six. It is cylindrical, with two longitudinal depressions, and has a small seed cavity that can easily be scooped out, leaving all the meat. Resistant to cracking, it ripens in 60 to 70 days in San Marzano's volcanic soil (80 to 100 days in the U.S.). More details were offered in 1920 by Ferruccio Zago, in his Nozioni di Orticultura: "The peeled tomato industry is a source of pride for Campania. People use a variety known as san marzano.... The plant can bear up to 10-12 bunches of fruit.... The skin has a bright red color and is easily removable, an indispensable characteristic for preparing peeled tomatoes. The pulp is dense and only slightly sugary in flavor...." In other words...it has less sugar!