Comments on: How to Kill Thrips Organically on Rhododendrons and Other Plants http://www.northcoastgardening.com/2009/06/how-to-kill-thrips-organically/ Helping you take joy in creating and maintaining the garden of your dreams... in the Pacific Northwest Wed, 10 Mar 2010 07:57:17 +0000 http://wordpress.org/?v=2.9.2 hourly 1 By: Iona http://www.northcoastgardening.com/2009/06/how-to-kill-thrips-organically/comment-page-1/#comment-1381 Iona Sat, 04 Jul 2009 23:18:10 +0000 http://www.northcoastgardening.com/?p=1219#comment-1381 You go girl!!!!!!!!!! <abbr><em>Iona’s last blog post..<a href="http://feedproxy.google.com/~r/blogspot/OFLn/~3/QWDK-Trgzno/please.html" rel="nofollow">Please</a></abbr></em> You go girl!!!!!!!!!!

Iona’s last blog post..Please

]]> By: Genevieve http://www.northcoastgardening.com/2009/06/how-to-kill-thrips-organically/comment-page-1/#comment-1378 Genevieve Sat, 04 Jul 2009 16:53:21 +0000 http://www.northcoastgardening.com/?p=1219#comment-1378 Hey Nels, the heads-up about the similarity of Thrips and Lace Bug damage is a great one. The difference between the damage caused by thrips and lace bugs is that lace bug damage is usually a lot coarser - more a mottling of the upper sides of the leaves than an overall silvery cast like with thrips. Scroll down on this link to see the mottled look of the lace bug damage: http://ipm.ncsu.edu/urban/cropsci/c09w_orn/rho_pest.html And here: http://oregonstate.edu/dept/nurspest/lacebug_damage_on_rhodies_medium_closeup.htm You can see that it's a bit more spotty than thrips damage, which is more a silvery cast: http://www.ipm.ucdavis.edu/PMG/H/I-TS-HHAE-CD.013.html As for thrips not being a pest outdoors in the coastal Pacific Northwest because it is too wet, that's not true. We get puh-lenty of water here in the redwoods and we do have thrips. I got some of this thrip info from my local Rhododendron nursery which definitely battles thrips, and has reported success with some thrip-specific biological controls. Thrips do hit plants that are dry with particular vigor, but the Pacific Northwest does have dry summers and that's when thrips are most active and most a pest here. Lastly, UC Davis reports that organic controls are effective on lace bugs, saying almost any insecticide will control lace bugs if it is sprayed directly onto the insects: http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7428.html More info on thrips for anyone interested: http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7429.html Hey Nels, the heads-up about the similarity of Thrips and Lace Bug damage is a great one. The difference between the damage caused by thrips and lace bugs is that lace bug damage is usually a lot coarser – more a mottling of the upper sides of the leaves than an overall silvery cast like with thrips.

Scroll down on this link to see the mottled look of the lace bug damage:
http://ipm.ncsu.edu/urban/cropsci/c09w_orn/rho_pest.html
And here:
http://oregonstate.edu/dept/nurspest/lacebug_damage_on_rhodies_medium_closeup.htm

You can see that it’s a bit more spotty than thrips damage, which is more a silvery cast:
http://www.ipm.ucdavis.edu/PMG/H/I-TS-HHAE-CD.013.html

As for thrips not being a pest outdoors in the coastal Pacific Northwest because it is too wet, that’s not true. We get puh-lenty of water here in the redwoods and we do have thrips. I got some of this thrip info from my local Rhododendron nursery which definitely battles thrips, and has reported success with some thrip-specific biological controls. Thrips do hit plants that are dry with particular vigor, but the Pacific Northwest does have dry summers and that’s when thrips are most active and most a pest here.

Lastly, UC Davis reports that organic controls are effective on lace bugs, saying almost any insecticide will control lace bugs if it is sprayed directly onto the insects:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7428.html

More info on thrips for anyone interested:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7429.html

]]> By: Nels Tronsen http://www.northcoastgardening.com/2009/06/how-to-kill-thrips-organically/comment-page-1/#comment-1377 Nels Tronsen Sat, 04 Jul 2009 14:53:48 +0000 http://www.northcoastgardening.com/?p=1219#comment-1377 Just figured you would want to know. That damage is not caused by thrips. Thrips are typically only an issue indoors in the Pac Northwest. Way too wet up here for the little buggers to be outside, typically. Anyway. the damage you described is caused by lace bugs, Stephanitis Rhododendri. And there is no way to rid your plants of them "organically". The bugs will feed on any stressed plants, i.e. drought or heavy sun exposure. they appear just after rhodie flowers drop in spring/summer as the new succulent leaves break out from there buds. So your best bet is to plant healthy varieties and remove susceptible species and maintain health and vigor of established plantings. <abbr><em>Nels Tronsen’s last blog post..<a href="http://www.northwestkind.com/2009/07/bees-in-borage.html" rel="nofollow">Bee's in the borage</a></abbr></em> Just figured you would want to know. That damage is not caused by thrips. Thrips are typically only an issue indoors in the Pac Northwest. Way too wet up here for the little buggers to be outside, typically. Anyway. the damage you described is caused by lace bugs, Stephanitis Rhododendri. And there is no way to rid your plants of them “organically”. The bugs will feed on any stressed plants, i.e. drought or heavy sun exposure. they appear just after rhodie flowers drop in spring/summer as the new succulent leaves break out from there buds. So your best bet is to plant healthy varieties and remove susceptible species and maintain health and vigor of established plantings.

Nels Tronsen’s last blog post..Bee’s in the borage

]]> By: Susan Morrison (garden-chick) http://www.northcoastgardening.com/2009/06/how-to-kill-thrips-organically/comment-page-1/#comment-1369 Susan Morrison (garden-chick) Fri, 03 Jul 2009 18:36:33 +0000 http://www.northcoastgardening.com/?p=1219#comment-1369 I always learn so much from your posts! Because I don't maintain the gardens I design, my knowledge of how to identify and treat plant diseases and infestations is minimal. Thanks for the great reminder that you can have a beautiful garden without requiring harsh pesticides to maintain it. <abbr><em>Susan Morrison (garden-chick)’s last blog post..<a href="http://feedproxy.google.com/~r/typepad/CIRU/~3/WxLg_Uy2YCA/s-love-better-the-second-time-around.html" rel="nofollow">Is Love Better the Second Time Around?</a></abbr></em> I always learn so much from your posts! Because I don’t maintain the gardens I design, my knowledge of how to identify and treat plant diseases and infestations is minimal. Thanks for the great reminder that you can have a beautiful garden without requiring harsh pesticides to maintain it.

Susan Morrison (garden-chick)’s last blog post..Is Love Better the Second Time Around?

]]> By: Monica http://www.northcoastgardening.com/2009/06/how-to-kill-thrips-organically/comment-page-1/#comment-1364 Monica Mon, 29 Jun 2009 13:03:04 +0000 http://www.northcoastgardening.com/?p=1219#comment-1364 I'm glad I don't have anything to add on thrips because I don't have them (knock wood). The only bugs that ever do any damage in my garden are Japanese beetles which like my (wait for it...) pussy willow! (I don't have roses.) They're never too bad, though, and I don't do anything to control them. <abbr><em>Monica’s last blog post..<a href="http://gardenfaerie.blogspot.com/2009/06/out-on-streets-june-2009.html" rel="nofollow">Out on the Streets: June 2009</a></abbr></em> I’m glad I don’t have anything to add on thrips because I don’t have them (knock wood). The only bugs that ever do any damage in my garden are Japanese beetles which like my (wait for it…) pussy willow! (I don’t have roses.) They’re never too bad, though, and I don’t do anything to control them.

Monica’s last blog post..Out on the Streets: June 2009

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