A widespread e-mail warning about termite-ridden mulch from New Orleans is nothing but a hoax, according to experts from Louisiana.

The e-mail, which has been making the rounds across North America, includes a dire warning about cheap mulch available at home and garden centres.

The e-mail says the mulch is made from termite-infested trees from hurricane-ravaged areas of Louisiana and could spread the destructive insect to homes and other structures.

Bob Odom, commissioner of Louisiana Department of Agriculture and Forestry, says he has no idea how the rumour started, but there is no way the e-mail's claim could be true.

"We put in a restriction immediately after the storm … and that restriction says that any trees or debris that leaves New Orleans has to go to a landfill, or is has to be certified by us to go to another landfill," he said.

"The reason we put the restriction in wasn't for the mulch. We had problems with rail road ties and other things leaving, that's why we put the restriction in," he added. "We didn't want somebody to buy a beam or something to put in their house and all of a sudden, it's infested with termites."

Odom says landfills in the area are monitored by security staff to make sure no unauthorized material leaves.

The labels on most bags of mulch or wood chips indicate the product's place of origin. If any type of insect is present in a bag of mulch, gardening experts recommend returning the bag to the store.