Volunteers are needed to help state preservationists identify and “weed” out invasive plants. Free training sessions are being held this month through Iowa State University and the state Department of Natural Resources. I-S-U forestry grad student Chris Evans says the volunteers will be dispatched to woodlands and forests across the Hawkeye State to find four types of plants: garlic mustard, Tartarian honeysuckle, common buckthorn and multiflora rose.All four plants can take over a forest and strangle every other plant in their path. Evans says the data collected over the next two years will be used to determine a strategy to manage the marauding plants. He says people who want to help won’t have to devote much time to the effort. He says it takes three to four hours for the training sessions. The free training sessions will be held this week at local conservation boards and interpretive centers. For more information, contact Evans at (515) 294-7125 or email to: “[email protected]”.