Integrated Pest Management Program Department of Plant Science and Landscape Architecture

UConn Extension

Tales from the Field, March 31, 2017 Leanne Pundt, Extension Educator, Greenhouse IPM In the previous message of March 24, I suggested checking for weekly emergence of the predatory mites (N. cucumeris) from the sachets based upon the tips in the Grower Guide: Quality Assurance of Biocontrol Products from the Vineland Research and Innovation Center in 2014. http://www.vinelandresearch.com/sites/default/files/grower_guide_pdf_final.pdf

Figure 1: Checking emergence of predatory mites, Photo by L. Pundt

I asked Shelley Durocher, Floriculture Grower and Research Laboratory Aide, from the UConn Floriculture Greenhouses for some additional tips, as Shelley mentioned that they have been doing this. Here are her suggestions:

I find that both the food and predatory mites sink into the adhesive on the sticky cards so it

makes it difficult to see them where there's even a raised area where a mite/insect might be on the card. With the use of a dissecting scope I can see not just the outline, but the shape and finer features of the individual mite as well, so I know which one I'm dealing with. I suppose with a higher magnification hand lens (30x or more) you could make close to the same determination as with the scope, but the wider range of view on the scope makes it a little easier.

I use the same technique as the one pictured in the photo you sent. I place the sachet stuck to the sticky card in the growing area so it is experiencing the same conditions as those in the pots. The binder clips are easy to remove from the card and place onto a new one so that the mites can be tracked from week to week. The biggest issue I have found is that because the predatory mites are so translucent, it can be had to see them on the cards without a dissecting scope.

Editors Note: I see more growers with dissecting scopes. You can often find inexpensive ones online. I also have one in my office, so could take a closer look for you, too.

Succulents are interesting in popularity, and they would seem to be relatively pest-free. But, I have seen melon aphids on sempervivum or hens and chicks in the past, and have been seeing root aphids this spring.

Figure 2: Melon Aphids on Sempervivum. Photo by L. Pundt

Figure 3: Root Aphids (within circle). Photo by L. Pundt

Root aphids (Pemphigus spp.) can also be found on other perennials such as Aster, Coreopsis, Lysimachia, Sedum and Veronica, to name a few. For more info:

Root aphids on Succulents: http://msue.anr.msu.edu/news/root_aphids_the_underground_pest_on_succulent_plants

Controlling Root Aphids with Botanigard: http://www.bioworksinc.com/products/shared/controlling-root-aphids-with-botanigard.pdf

Greenhouse Lunch-time Webinar: How to Identify and Manage Iron Deficiency and Toxicity in Spring Greenhouse Crops Wednesday, April 19, 2017 - 12:00 pm to 12:30 pm

Nutrient and pH management is challenging, especially when growing multiple crops with different needs in the same greenhouse. Iron deficiency and toxicity symptoms are common on some spring crops in greenhouses. In this 30 minute webinar Dr. Rosa Raudales (Assistant Professor and Greenhouse Extension Specialist, University of Connecticut) will discuss how to identify and manage the symptoms of iron deficiency and toxicity on spring greenhouse crops. Link to webinar: https://attendee.gotowebinar.com/register/3040408417633767937 Question? Contact: Geoffrey Njue: 413-992-8005 gnjue@umext.umass.edu University of Massachusetts Extension Organic Fertilization of Vegetable Bedding Plants More growers are fertilizing a portion of their vegetable bedding plants organically in response to customer interest. For more information: New England Vegetable Management Guide https://nevegetable.org/ Go to the Growing Media and Nutrition section of Growing Vegetable Transplants: https://nevegetable.org/vegetable-transplant-production/growing-media-and-nutrition Mattson, Neil. Substrates and Fertilizers for Organic Vegetable Transplant Production http://www.greenhouse.cornell.edu/crops/organic.html

If you missed Doug Cox’s webinar on How to Use Nature’s Source and Sustane Organic Fertilizers, it is now online at the UMass website: Webinar https://ag.umass.edu/greenhouse-floriculture/education-events/webinars Generally, a combination of products including a granular product and liquid one, seem to work best. Disclaimer for Fact Sheets:

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