Air-bomb seedlings for La. marshlands

PORT FOURCHON, La. - A crop duster took aim at Sarah Mack's boat across a salt marsh near Port Fourchon. The aircraft swooped low, dropping thousands of little green pods, which plopped into the marsh and shoreline. Tierra Resources, a wetland restoration company, is trying a new tactic in the fight against coastal land loss – dropping mangrove seedlings into the marshland. Mack, Tierra's founder, led crews that spent last week gathering a half-million of propagules seedlings, to spread across the marshes, a hub for oil shipping in the northern Gulf of Mexico. Unlike the grasses dominating the marsh, mangrove trees put down sturdy roots that are more resistant to erosion. Planting by hand would have been too costly and time-consuming in the marshes of Lafourche and Terrebonne parishes. Over the last 80 years, Louisiana has lost about 2,000 square miles of coastal marsh. The reasons are numerous: Erosion and saltwater intrusion caused by oil and gas exploration, hurricanes, and the Mississippi River's extensive levee system, which blocks wetland-building sediment. Air-seeding mangroves cost about $3,000 per acre. Other methods of restoration could be as much as $150,000 per acre. Tierra began planting mangroves in 2012 at the invitation of ConocoPhillips. The company owns about 640,000 acres of marshland in Louisiana. Much of ConocoPhillips' marsh is receding, putting its sizeable investments - oil and gas wells, pipelines, refineries and port facilities - at risk. ConocoPhillips provided much of Tierra Resources' startup costs. Funding expanded to include Entergy Corp. and other partners after air seeding showed positive results last year. (Source: NOLA.com 11/08/17)