Re: Bud pin worms

>A local japanese iris grower lost most of last year's bloom to a worm that
>tunneled into the bud and ruined the bloom.
>
>Can anyone give a more intelligent description of the pest we're talking
>about and what controls are effective?
>
>Thank you!
>
>Kathyguest, E. Aurora, NY
****
	It sounds like the Iris Bud Fly (Orthochaeta dissimilis) that
	feasts on beardless iris buds. There was a discussion last year
	on the list about it....I think Chris Hollinshead and I both
	lost buds. I lost buds on both Japanese and Siberians. This was the

	second year - different plants. One of the JI's that was attacked
	in '95 bloomed normally in '96. No lasting damage. In my garden, the
	'fly' seems to prefer the older varieties - I am sure it is a coin-
	cidence (?).

	From 'The Siberian Iris':

 	"The larva of Orthochaeta dissmilis is a white maggot approx-
	0.10 inch (3 millimeters) long, cone-shaped, smooth and white, with
	a small black dot at the pointed end and the larger end rather flat.
	Presence of the iris bud fly us first evident when an apparently
	normal bud opens to reveal ragged, chewed standards and styles. A
	careful search conducted just after the flower opens may turn up
	the larva, hidden under the damaged styles. Only a few hours later
	the larva will be gone, having crawled or dropped into the spathes.
	Rarely it may invade the ovary before settling in the spathes, where
	it pupates and remains over winter; the adult fly emerges the next
	spring. Dimethoate is effective appied ar the same rate as for borer
	control, except that plants should be sprayed just as the earliest
	siberian irises form buds. If infected flowers are found, cut off
	the stalks bearing affected flowers well below the spathes and burn
	them."  p. 64, McEwen

	McEwen says that the iris bud fly was first reported by Sarah
	Tiffney (1978) in Massachusetts and seems to be increasing in Maine
	and in other parts of New England *and* Hoebeke puts it in Western
	New York in 1994....Hoebeke holds that the O.d. occurs only in
	North America and suspects that a related fly species (Acklandea
	servadeii) damages irises in Europe where it is known as the iris
	flower bud fly.

	I did not spray my JIs and SIs with anything since I use no chemicals
	in gardening....

	Ellen
































	------------------------------------------------------------------------------

Ellen Gallagher	\ e_galla@moose.ncia.net \ Lancaster, New Hampshire,USA
  USDA Zone 3a \ Northern White Mountains\ AIS Region 1 {New England}
Other Mailing lists | Author Index | Date Index | Subject Index | Thread Index