I just read this article in the 07/18/02 edition of the Boston Globe.
Noticed this last month with some of my lilies, but had no idea what was going on.
Sorry if someone posted this already, even so maybe someone new will see this.
****************************************************
Lilies losing battle against a new pest from Europe
By Carol Stocker, Globe Staff, 7/18/2002
What's eating my lilies?
That's one of the most frequently asked questions in local garden centers.
If it's bright red and shiny as a fire engine with a black head and legs, and it squeaks if you pinch it, your lilies are under attack by the lily leaf beetle (Lilioceris lilii).
This new pest from Europe was first reported in the United States in 1992 here in Cambridge. Since then, it has spread about 10 miles a year from ground zero, except when it hitches a ride on some retailer's potted plants. It's now reached all six New England states and New York, though coverage is spotty, and every year it makes its first appearance in thousands of gardens. The tell-tale sign is lilies that have been stripped of their foliage.
Without human intervention, the lilies will continue to sprout each spring for several years before giving up, but they will be so tattered that they will have zero aesthetic appeal in the meantime. (Except for one resistant variety that I'll get to later.)
What you do depends upon how attached you are to your lilies. Your choice is to fight or surrender.
When you walk through a neighborhood the beetles have not yet reached that is festooned with summer lilies, a place such as Provincetown, it seems like a no-brainer that lilies are worth fighting for. They are one of the essential flowers of summer, especially the large white Casablanca lilies that bloom in August when almost nothing else does, scenting the air with a powerful yet refined fragrance.
In fact, lily leaf beetles are easy to kill. The problem is that new ones are always flying in from the neighbor's yard, so you have to keep at it. So though most gardeners start out in combat mode, they usually give up, overwhelmed by the relentless red tide.
Lily leaf beetles will feed lightly on many plants including Solomon's seal, lily-of-the-valley, hosta, potato leaves, and flowering tobacco. However, they will lay their irregular lines of orange eggs only on the undersides of the leaves of lilies and fritillaria, another hardy plant that grows from bulbs that you might not want to purchase anymore. (Lily leaf beetles don't touch daylilies, which look similar but are not true lilies.)
The lily leaf beetle adult is a beautiful insect with a bright red back. Every other part of its body - legs, head, antennae, belly - is black. Adult beetles are one-quarter to three- eighths inches long, about the size of a ladybug, only skinny instead of rotound.
Female beetles can live two years and lay as many as 450 eggs, which hatch in about a week. The immature larva is as ugly as the adult is beautiful. These grubby things resemble slugs with tiny black heads, and they carry their excrement on their backs to deter predators. They look as if they've been tarred. And they do more damage than the adults.
After eating your lilies for two or three weeks, the larvae go underground and emerge as adults after a couple more weeks. The new adults continue eating lilies until fall, flying off to new gardens when your lilies are stripped. After hibernating through the winter, they re-emerge the following spring between March and June.
If you have only a few plants in your garden, you can hand-pick the adults. One method is to hold a jar of soapy water under the bright red beetle and give its perch a little jiggle. The beetle will drop like a stone into the jar and drown.
The most energy-effective approach is to look for those orange-red eggs on the underside of lily and fritillaria leaves next year and squish them before they hatch, or snip off the egg-laden leaves and remove them. You'll find the most eggs at the end of May, but you may see them anywhere between mid-April and the beginning of July.
Any poison that will kill beetles will kill lily leaf beetles. The insecticides Sevin and Malathion work on both adults and larvae. However, Sevin also kills bees, and Malathion is also toxic to many beneficial insects.
Entomologist Richard Casagrande of the University of Rhode Island, a specialist in the lily leaf beetle, recommends treating flowers with neem, a much less toxic chemical based upon natural extracts from the neem tree. Neem can be purchased at garden centers under the trade names Turplex, Azatin EC, Margosan-0, Align, and BioNeem. Neem kills larvae and repels adults. It is most effective on young larvae and must be applied weekly, June through July.
The insecticide Merit (imidacloprid) also provides effective control and needs to be applied only once, preferably in the spring. It is available in several formulations from Bayer including foliage sprays, soil drenches, and fertilizer stakes.
The lily leaf beetle is having a field day because it has no apparent natural predators here. Lily lovers hope that is about to change. Casagrande is directing current efforts to introduce natural predators from Europe, where at least four species of parasitoids keep lily leaf beetles effortlessly under control.
Casagrande's team already has released one species of European parasitoid, a minute wasp called Tetrstichus setifes, at Elm Bank in Wellesley, the new home of the Massachusetts Horticultural Society, and at the University of Massachusetts experimental station in Waltham. This parasitoid lays its eggs inside live lily leaf beetle larvae. It survived last winter here and now may be permanently established, though it will probably take a few years to reach your yard. If you live near Wellesley or Waltham, Casagrande says, don't spray insecticides and don't mulch your lilies because both these practices will cut down on the wasp's ability to survive and spread here. (It needs to hibernate over the winter in open ground under lilies, and mulching keeps it from doing this.)
Casagrande says his team will probably distribute the wasps through organizations such as the Massachusetts Horticultural Society, the New England Lily Society, and through research cooperatives.
''This will give us a handle on where they are and how well they establish,'' he said. ''Our goal is to get them spread throughout the infested area as soon as reasonably possible. This should take at least several years. We're being very cautious.''
Casagrande also wants to get a second type of parasitoid established that will attack lily leaf beetles at a different time of year.
''Everywhere in Europe, there was a complex of at least two different parasitoides, an early one and a late one. We are conducting basic experiments on parasite biology and host specificity with the other parasitic insects in our quarantine laboratory on campus, perhaps eventually leading to additional releases in the USA,'' he said. The work so far has been funded by the North American Lily Society, White Flower Farm, The Rhode Island Nursery/Landscape Association, a USDA competitive grant, and the Rhode Island Agricultural Experiment Station.
I gave up my expensive hybrid lilies without a fight. I garden organically, so I won't spray, and I decided at the outset that I didn't want to invest the time in hand-picking the beetles.
I'm waiting for Casagrande's little wasps to establish themselves in Boston. Then I'll order more Casablanca lily bulbs. In the meantime, I've just ordered three Black Beauty lily bulbs over the Internet from www.walmart.com for $6.95 each. These are giant, late-blooming, red-black, Oriental lilies with stalks as thick as broomsticks and are known for their vigor, if not their grace. They are tetraploids, meaning they have double the normal number of chromosomes. Casagrande says that in his test plots, these are the only lilies that the lily leaf beetles haven't touched.
For more information, visit the University of Rhode Island Cooperative Extension Web site at uri.edu/ce/factsheets/sheets/lilyleafbeetle.html. A USDA-funded map showing the spread of the LLB can be found at http://www.ceris.purdue.edu/napis/pests/pboard/imap/llball.html.
Footnote: The new Blackwell Footpath across Bussey Brook Urban Wild linking the Forest Hills MBTA Station to the Arnold Arboretum has been named after John Blackwell, founding director of the Boston Natural Areas Fund (now Network), which is celebrating its 25th anniversary this year. In 1981, Blackwell, who pioneered efforts to preserve Boston's urban wilds, developed a strategy to protect the land of the 20-acre Bussey Brook Urban Wild owned by Harvard University, the City of Boston, and the MBTA and use the site to provide comfortable pedestrian public access through the natural area to the Arboretum. The completed paved and landscaped path is nearly a half-mile long with handsome granite and wrought-iron entrance gates at New Washington Street and South Street across from the Arboretum entrance.
This story ran on page H1 of the Boston Globe on 7/18/2002.
© Copyright 2002 Globe Newspaper Company.
Noticed this last month with some of my lilies, but had no idea what was going on.
Sorry if someone posted this already, even so maybe someone new will see this.
****************************************************
Lilies losing battle against a new pest from Europe
By Carol Stocker, Globe Staff, 7/18/2002
What's eating my lilies?
That's one of the most frequently asked questions in local garden centers.
If it's bright red and shiny as a fire engine with a black head and legs, and it squeaks if you pinch it, your lilies are under attack by the lily leaf beetle (Lilioceris lilii).
This new pest from Europe was first reported in the United States in 1992 here in Cambridge. Since then, it has spread about 10 miles a year from ground zero, except when it hitches a ride on some retailer's potted plants. It's now reached all six New England states and New York, though coverage is spotty, and every year it makes its first appearance in thousands of gardens. The tell-tale sign is lilies that have been stripped of their foliage.
Without human intervention, the lilies will continue to sprout each spring for several years before giving up, but they will be so tattered that they will have zero aesthetic appeal in the meantime. (Except for one resistant variety that I'll get to later.)
What you do depends upon how attached you are to your lilies. Your choice is to fight or surrender.
When you walk through a neighborhood the beetles have not yet reached that is festooned with summer lilies, a place such as Provincetown, it seems like a no-brainer that lilies are worth fighting for. They are one of the essential flowers of summer, especially the large white Casablanca lilies that bloom in August when almost nothing else does, scenting the air with a powerful yet refined fragrance.
In fact, lily leaf beetles are easy to kill. The problem is that new ones are always flying in from the neighbor's yard, so you have to keep at it. So though most gardeners start out in combat mode, they usually give up, overwhelmed by the relentless red tide.
Lily leaf beetles will feed lightly on many plants including Solomon's seal, lily-of-the-valley, hosta, potato leaves, and flowering tobacco. However, they will lay their irregular lines of orange eggs only on the undersides of the leaves of lilies and fritillaria, another hardy plant that grows from bulbs that you might not want to purchase anymore. (Lily leaf beetles don't touch daylilies, which look similar but are not true lilies.)
The lily leaf beetle adult is a beautiful insect with a bright red back. Every other part of its body - legs, head, antennae, belly - is black. Adult beetles are one-quarter to three- eighths inches long, about the size of a ladybug, only skinny instead of rotound.
Female beetles can live two years and lay as many as 450 eggs, which hatch in about a week. The immature larva is as ugly as the adult is beautiful. These grubby things resemble slugs with tiny black heads, and they carry their excrement on their backs to deter predators. They look as if they've been tarred. And they do more damage than the adults.
After eating your lilies for two or three weeks, the larvae go underground and emerge as adults after a couple more weeks. The new adults continue eating lilies until fall, flying off to new gardens when your lilies are stripped. After hibernating through the winter, they re-emerge the following spring between March and June.
If you have only a few plants in your garden, you can hand-pick the adults. One method is to hold a jar of soapy water under the bright red beetle and give its perch a little jiggle. The beetle will drop like a stone into the jar and drown.
The most energy-effective approach is to look for those orange-red eggs on the underside of lily and fritillaria leaves next year and squish them before they hatch, or snip off the egg-laden leaves and remove them. You'll find the most eggs at the end of May, but you may see them anywhere between mid-April and the beginning of July.
Any poison that will kill beetles will kill lily leaf beetles. The insecticides Sevin and Malathion work on both adults and larvae. However, Sevin also kills bees, and Malathion is also toxic to many beneficial insects.
Entomologist Richard Casagrande of the University of Rhode Island, a specialist in the lily leaf beetle, recommends treating flowers with neem, a much less toxic chemical based upon natural extracts from the neem tree. Neem can be purchased at garden centers under the trade names Turplex, Azatin EC, Margosan-0, Align, and BioNeem. Neem kills larvae and repels adults. It is most effective on young larvae and must be applied weekly, June through July.
The insecticide Merit (imidacloprid) also provides effective control and needs to be applied only once, preferably in the spring. It is available in several formulations from Bayer including foliage sprays, soil drenches, and fertilizer stakes.
The lily leaf beetle is having a field day because it has no apparent natural predators here. Lily lovers hope that is about to change. Casagrande is directing current efforts to introduce natural predators from Europe, where at least four species of parasitoids keep lily leaf beetles effortlessly under control.
Casagrande's team already has released one species of European parasitoid, a minute wasp called Tetrstichus setifes, at Elm Bank in Wellesley, the new home of the Massachusetts Horticultural Society, and at the University of Massachusetts experimental station in Waltham. This parasitoid lays its eggs inside live lily leaf beetle larvae. It survived last winter here and now may be permanently established, though it will probably take a few years to reach your yard. If you live near Wellesley or Waltham, Casagrande says, don't spray insecticides and don't mulch your lilies because both these practices will cut down on the wasp's ability to survive and spread here. (It needs to hibernate over the winter in open ground under lilies, and mulching keeps it from doing this.)
Casagrande says his team will probably distribute the wasps through organizations such as the Massachusetts Horticultural Society, the New England Lily Society, and through research cooperatives.
''This will give us a handle on where they are and how well they establish,'' he said. ''Our goal is to get them spread throughout the infested area as soon as reasonably possible. This should take at least several years. We're being very cautious.''
Casagrande also wants to get a second type of parasitoid established that will attack lily leaf beetles at a different time of year.
''Everywhere in Europe, there was a complex of at least two different parasitoides, an early one and a late one. We are conducting basic experiments on parasite biology and host specificity with the other parasitic insects in our quarantine laboratory on campus, perhaps eventually leading to additional releases in the USA,'' he said. The work so far has been funded by the North American Lily Society, White Flower Farm, The Rhode Island Nursery/Landscape Association, a USDA competitive grant, and the Rhode Island Agricultural Experiment Station.
I gave up my expensive hybrid lilies without a fight. I garden organically, so I won't spray, and I decided at the outset that I didn't want to invest the time in hand-picking the beetles.
I'm waiting for Casagrande's little wasps to establish themselves in Boston. Then I'll order more Casablanca lily bulbs. In the meantime, I've just ordered three Black Beauty lily bulbs over the Internet from www.walmart.com for $6.95 each. These are giant, late-blooming, red-black, Oriental lilies with stalks as thick as broomsticks and are known for their vigor, if not their grace. They are tetraploids, meaning they have double the normal number of chromosomes. Casagrande says that in his test plots, these are the only lilies that the lily leaf beetles haven't touched.
For more information, visit the University of Rhode Island Cooperative Extension Web site at uri.edu/ce/factsheets/sheets/lilyleafbeetle.html. A USDA-funded map showing the spread of the LLB can be found at http://www.ceris.purdue.edu/napis/pests/pboard/imap/llball.html.
Footnote: The new Blackwell Footpath across Bussey Brook Urban Wild linking the Forest Hills MBTA Station to the Arnold Arboretum has been named after John Blackwell, founding director of the Boston Natural Areas Fund (now Network), which is celebrating its 25th anniversary this year. In 1981, Blackwell, who pioneered efforts to preserve Boston's urban wilds, developed a strategy to protect the land of the 20-acre Bussey Brook Urban Wild owned by Harvard University, the City of Boston, and the MBTA and use the site to provide comfortable pedestrian public access through the natural area to the Arboretum. The completed paved and landscaped path is nearly a half-mile long with handsome granite and wrought-iron entrance gates at New Washington Street and South Street across from the Arboretum entrance.
This story ran on page H1 of the Boston Globe on 7/18/2002.
© Copyright 2002 Globe Newspaper Company.
