Wild Ones   The Grapevine - September-October 2006  
By Maryann Whitman

Invasive and destructive gypsy moths fall prey to a "fungus among us." Homeowners begin to realize that their lawns really do suck (too much water). And does NASA still go where no one has gone before?

Surprise, surprise

GrapevineWhen populations of gypsy moths reach outbreak proportions, the caterpillars can completely defoliate host trees over a wide geographic area. Consistent or repeated defoliation over several years can have devastating effects, often leading to tree stress and death.

Gypsy moths have a wide host-range, which includes oak (Quercus sp.), crabapple (Malus sp.), linden (Tilia sp.), poplar (Populus sp.), beech (Fagus sp.), willow (Salix sp.), birch (Betula sp.), sweetgum (Liquidambar styraciflua), serviceberry (Amelanchier sp.), and hawthorn (Crataegus sp.). Trees less-susceptible to attack by gypsy moth are ash (Fraxinus sp.), sycamore (Platanus sp.), indian bean (Catalpa sp.), honeylocust (Gleditsia sp.), dogwood (Cornus sp.), junipers (Juniperus sp.), yew (Taxus sp.), lilac (Syringa sp.), arborvitae (Thuja sp.), arrowwood (Viburnum sp.), and tulip tree (Liriodendron tulipifera).

Conifers are more susceptible to death than deciduous trees because they don’t produce another flush of growth once defoliated. Conifers, such as pine (Pinus sp.) and spruce (Picea sp.), are unable to produce new leaves (needles) after defoliation as compared to deciduous trees. As a result, conifers can die after one severe defoliation.

The ecological and economic impact of gypsy moths is a serious concern. Gypsy moth defoliation can change the complexity of understory growth thus resulting in an increase or decrease of certain fauna or flora. Defoliation may predispose trees to attack by opportunistic insects or diseases. For example, Gypsy moth feeding can increase a tree’s susceptibility to the attack by the shoestring fungus, Armillariella mellea and the two-lined chestnut borer, Agrilus bilineatus.

While major damage has tended to occur in the Northeast and Upper Midwest, gypsy moths are caught in pheromone traps across the country. This indicates that they are continually present at low levels in scattered locations across the United States.

Native to Asia and Europe, gypsy moths were accidentally introduced into the Boston area in 1868 or 1869, (the fellow thought they might help him make his fortune in the silk industry – but that’s another story). Apparently they were causing enough damage in the New England States for desperate measures to be taken in 1910 and 1911 – a fungus (Entomophaga maimaiga), known to affect only Japanese gypsy moths was introduced in Massachusetts. And then the fungus disappeared.

New information out of Cornell University, Department of Entomology confirms that the fungus is still alive and well. It surfaced again in 1989, when gypsy moth larvae were found dying and dropping out of the trees.

The fungus has had a century of opportunity, but does not seem to infect any other Lepidoptera. Now it’s just a matter of figuring out how to harvest, reproduce and spread the fungus in the infested areas.

Lawn Gone: Homeowners rethink their water-sucking lawns

A “delawning” movement is sprouting up around the United States, as a handful of homeowners switch from resource-intensive grassy green expanses to drought-tolerant, native, and/or edible gardens.“It’s about shifting ideas of what’s beautiful,” says Fritz Haeg, a Los Angeles architect whose Edible Estates project transforms front yards into fruit and vegetable gardens. A new report from the Public Policy Institute of California provides more fodder for the anti-lawn set. It asserts that thirsty home landscaping will suck up a troubling amount of water in the state over the next 25 years if the love affair with lawns continues. California is expected to add 11 million new residents by 2030, with at least 50% settling in hotter inland regions where single-family homes with lawns are common, according to the report. Some neighbors, however, don’t appreciate creative gardening. “What happens in the backyard is their business,” said one man who lives near a yard now being used to grow 195 various edibles. “But this doesn’t seem to me to be a front yard kind of a deal.”

NASA Lapso: NASA deletes planet-protecting phrasing from mission statement.

The phrase “to understand and protect our home planet” was quietly deleted from NASA’s mission statement in February. The agency’s mission now is “to pioneer the future in space exploration, scientific discovery, and aeronautics research.” NASA’s 19,000 employees were neither consulted nor informed ahead of time of the deletion. The planet-protection phrase had been added to the mission statement in 2002. Scientists say it shaped research priorities, and the deletion will reduce incentive for research on phenomena like – oh, to pick one at random – climate change.

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“Lawn Gone” and “NASA Lapso” reprinted by permission from Grist Magazine (www.grist.org). For more environmental news and humor, sign up for Grist’s free e-mail service, www.grist.org/signup.

Maryann is Editor of the Wild Ones Journal, and comes to the position with an extensive background in environmental matters of all kinds.

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