SACRAMENTO, Calif.— Agents have seized more than $2.6 billion worth of marijuana plants this year, already surpassing last year's season total by 20 percent, authorities said. The state Department of Justice's annual Campaign Against Marijuana Planting, or CAMP, is still a month away from wrapping up operations after the season peak at the end of September. The raids, many in remote, forested terrain, pit agents against often heavily armed guards protecting their marijuana plots. About three weeks ago, a grower was shot dead and a state Fish and Game warden was wounded during a raid on a 22,000-plant pot farm...