Scouting Is More Than Looking For Insects

Coleus2_siktberg

Catching problems before they become problems in a greenhouse requires a trained eye and a regular routine of monitoring plant health. While scouting is most often thought of as checking for insect pests, in broader terms it means monitoring overall plant health – checking for nutrient deficiency symptoms, under or overwatering, hot spots or cold spots in the greenhouse, sanitation problems and detection of disease pathogens. Scouting is at the core of any IPM program and is an essential best management practice for greenhouse operations. While record keeping and data collection may not be on your list of favorite things to do, the headaches saved down the road by catching problems early make it well worth your time.

“It’s not just scouting for insects and diseases,” says Kelly Ivors, associate professor and extension specialist at the Department of Plant Pathology at North Carolina State University. “It’s also scouting for healthy plants. It’s checking for healthy growing conditions such as monitoring temperature.”
Ivors stresses the importance of knowing what your plants are supposed to look like.

“For instance, there’s a lot of different varieties of coleus, and sometimes it’s easy to mistake [their variegation] for a disease or nutrition problem. But that might be the way they’re supposed to look,” she says. “You really need to know what that plant is supposed to look like when you’re working with floriculture and herbaceous plants because there’s so much variety.”

Overall plant health is important because a healthy plant can ward off some of the secondary, or opportunistic pathogens, on its own. These are things that aren’t typically problems unless you have other problems, Ivors says.

“For example, there are a few species of pythium that aren’t always a problem, but they can be if fertility is off, if there’s salt damage or if there are some odd temperature fluctuations,” she says. “You can [also] get botrytis really badly in a greenhouse if you have wounded plant tissue from cold temperatures.”

While scouting for insects may often involve measuring levels of the population and keeping it below acceptable thresholds, once a potential disease problem is identified, action is often taken early because diseases can spread so quickly.

“Look for wilting, for stunting, for yellowing leaves,” Ivors says. “Anything that looks abnormal.” Leaves that are off-color or have spotting are also signs of a problem, she says.

Once you notice something odd, it’s important to get the correct diagnosis, which often involves sending samples to a plant pest and disease clinic.

“Half the things we get in our clinic aren’t even diseases or insects – they’re cultural things. But growers are willing to send samples in to get that confirmed because they know it could be a big problem if it is a disease,” Ivors says.

The location and spread of symptoms often offer a clue to the type of problem.

“You have to look at the consistency of the problem across the entire crop,” Ivors says. “If it’s affecting the whole crop, it’s probably a cultural problem. Often diseases don’t show up with that kind of uniformity unless perhaps you propagated from infected material.”

Ivors points out that this is where good record keeping becomes important, stating that for diseases, comparing the time of day, the symptoms and location of the problem can then be compared with pest control and fertilizer applications, as well as with temperature and humidity records to see if there might be a connection, such as a phytotoxicity issue with a plant growth regulator or fungicide.

Diligent, regular scouting by someone trained in what to look for buys time and allows more options for control, Ivor says, because you can prevent the problem rather than trying to apply something curative.

“A lot of fungicides do not have curative activity. If you don’t scout and don’t catch the problem until it’s at a very high level, it’s very difficult to control at that point,” she says.

Ivors cites powdery mildew as a good example of this.

“There are a lot of products that are very good at protecting plants that aren’t yet infected,” she says. “But it’s very difficult to wipe out the disease once it’s been established.”

Leave a Reply

3 comments on “Scouting Is More Than Looking For Insects

  1. I enjoyed this article. I am a Horticulture instructor at Fox Valley Technical College, Appleton, WI. I am teaching a Plant Diagnostics course and I have been going over the importance of scouting with my class. It is good for the students to see another opinion that backs up what I tell them. Thanks for your article, I look forward to many more.

  2. When scouting it's also important to use your nose to smell for the frass of the fern worms in high up baskets and to detect natural gas leaks that might be occurring in the greenhouse. Also use your eyes to watch folks water to see if fertilizer dye is coming through the line. A jar test is valuable too to see if water is clear or blue.

Latest Stories
Jim Devereux, Green Fuse Botanicals

June 24, 2017

Green Fuse Botanicals New Vice President is Focused on …

Jim Devereux, who will oversee production, sales, and marketing for Green Fuse, says he hopes to bring genetics to the market that break from traditional production methods for finished growers.

Read More
Greenbelt Microgreens

June 23, 2017

Greenbelt Microgreens is a Finalist for the 2017 Operat…

Winner of the Excellence in Innovation Award, Greenbelt Microgreens is constantly staying on top of the latest trends in technology,

Read More
Ushio Sakazaki feature

June 22, 2017

Japanese Breeder Ushio Sakazaki Wins Medal of Excellenc…

From Supertunias to Superbells, this innovative Japanese breeder has used wild genetics to create game-changing plants that help consumers reconnect with the beauty of nature.

Read More
Koppert Ulti-Mite Swirski sachet

June 21, 2017

New Tool from Koppert Provides More Effective Thrips Ma…

A newly patented sachet for the predatory mite Amblyseius swirskii is resistant to both low and high levels of humidity, helping growers combat thrips infestations.

Read More
CallaFornia Red

June 20, 2017

Dümmen Orange Enters Calla Market With Acquisition of G…

Golden State will continue to supply the market through September 2018, at which time Dümmen Orange will assume supply and delivery of much of Golden State’s product line.

Read More

June 20, 2017

Sign Up For The Luxflora Flower Run At Cultivate’17

The5k walk/run race, sponsored by Luxflora, is an opportunity for industry members to network, build relationships, have some healthy fun, and start off Cultivate’17 with a flourish.

Read More

June 19, 2017

IGC Show Features Talks on How to Cash in on the Buy Lo…

This year’s event, which takes place Aug. 15-17 in Chicago, also includes a free workshop on what you might do when starting your business over from scratch.

Read More
SNA Logo

June 19, 2017

SNA, MANTS Plan to Co-Locate Their Events in 2018

There is crossover appeal for participants of both events, according to show organizers, and this cooperation will bring value and potential new business opportunities for both audiences.

Read More
Heat Safety App

June 18, 2017

Protect Your Employees from Heat-Related Illnesses with…

The National Institute for Occupational Safety and Health and the Occupational Safety and Health Administration have released an updated app for smart phones that can help workers stay safe when working outdoors in hot weather.

Read More
Visser Autostix

June 17, 2017

Visser, Ball Partner on New Sticking Technology for Cut…

The new AutoStix system is designed to provide better consistency and uniformity with shipped cuttings, easier and more reliable counting, automatic transplanting, and optional buffering in the peak season.

Read More
sbi-software-triumph

June 16, 2017

Five Guidelines to Investing in Software for Your Green…

Any software improvement you make should make sense for your team and be worth the investment.

Read More
EOE-featureimage2017

June 15, 2017

Greenhouse Grower’s 2017 Evening Of Excellence Will Rec…

Registration is now open for the 2017 Greenhouse Grower Evening Of Excellence, which takes place Monday, July 17, during Cultivate’17.

Read More
Plantpeddler Variety Day

June 14, 2017

Plantpeddler Hosting Variety Day on Aug. 4 in Cresco, I…

The free event will allow attendees to tour Plantpeddler’s trial gardens, which include more than 1,200 varieties of vegetative annuals displayed in large containers, baskets, window boxes, and beds.

Read More
Iron and Manganese toxicity in geranium

June 13, 2017

Are Your Geraniums Showing Signs of Iron or Manganese T…

Zonal geraniums with low pH can exhibit iron and manganese toxicity symptoms, including marginal chlorosis, leaf speckling, and upward-cupping of the leaves, according to Michigan State University experts.

Read More
weed sanitation

June 13, 2017

New Research Explores Potential of Using Steam or Hot W…

USDA-Agricultural Research Service horticulturist Dr. James Altland is exploring an alternative method for controlling weeds in greenhouse propagation systems by using steam or hot water to kill weed seeds.

Read More
Paul Fisher Fertilizer feature

June 12, 2017

How to Improve Customer Success by Adding Residual Fert…

Even if it costs a few cents more per pot or extra labor, your customers will thank you with repeat sales.

Read More
Jonathan Babikow, Emerald Coast Growers

June 9, 2017

New Head Grower at Emerald Coast Growers is Excited abo…

Jonathan Babikow, Emerald Coast Growers’ new general manager/head grower for its Lancaster, PA, location, talks about his favorite perennials, the advantages of growing in Pennsylvania, and his future hopes for his career.

Read More
Petunia 'Amore Mio' (Danziger)

June 8, 2017

AmericanHort Update on Genetically Engineered Petunias

AmericanHort is actively assisting affected plant breeders, distributors, growers, and retailers as the genetically modified petunia regulatory response continues. Since the last update, there have been several changes to the list of petunias confirmed or suspected of being genetically engineered and therefore unauthorized to be imported or sold. Also, the list of recognized laboratories for petunia variety confirmation testing has expanded. Most importantly, petunia varieties on the USDA-APHIS Biotechnology Regulatory Services (BRS) list require an APHIS Form 2000 for importation. APHIS also began requiring that any Petunia spp. Shipments, not including regulated GE varieties, must be accompanied by a list of variety names. This resulted in some inspection delays at the USDA-APHIS plant inspection station in Atlanta over the past two weeks. In response, AmericanHort has negotiated a more flexible approach with APHIS, and new guidance has just been posted for importing Petunia plants, cuttings, or seed. The new guidance allows […]

Read More