Sunlight hits frost on the windows inside the Horridge Conservatory. Temperature outside was 5 degrees F.

Greenhouse scouting: Integrated Pest Management – IPM – relies on information gathered through scouting, or monitoring,  to make decisions about which pest control measures should be taken. I wrote about our greenhouse IPM program in this post last winter. I am happy to report that there are fewer, much fewer, insects than last winter. Of course, there are the usual “bad guys” — but not so many.

From the Ohio State University Extension:

“The person who performs the field scouting activity in an IPM program is referred to as the “field scout.” This individual is responsible for collection of field observations and may or may not be responsible for making pest management recommendations. In some IPM programs, it is the field scout’s role to collect field observations but not provide recommendations.

The tasks of the field scout include (1) making accurate identifications of pests and related crop injury present in the field, (2) determining the abundance of the pest populations and degree of injury present, (3) noting relevant parameters related to crop development, and (4) recording all field observations in a manner that can be forwarded to the party making the final decisions regarding pest management actions to be taken.”

I have been scouting the greenhouses each week — systematically going through each one, looking for anything out of the ordinary. We tend to have insect pests but very little in the way of diseases through the winter in our greenhouses. Once I get a good picture of which pests are present, I can make decisions about what management or control strategy to use. The IPM approach means that we start with the “least toxic” methods, which is often as simple as a soap and water spray.

Last winter’s application of Steinernema feltiae, a microscopic nematode which attacks  the larvae of Western Flower Thrips, has resulted in a lower population of thrips this year. Cabbage worms (A strange thing in the greenhouse in January!) on the coleus are big enough to hand pick into a bucket of soapy water. For insects such as scales and mealybugs, ultra refined oil spray is an ecologically good choice because it’s mode of action is mechanical (the thin coating of oil smothers the insects) rather than chemical. This means that pests cannot develop resistance to it. It is also much safer for the greenhouse staff and visitors.

Scouting is part of the fun of working in the greenhouse. I enjoy the detective work of identifying what is causing problems for the plants, whether it is insects, disease, or environment. Then figuring out what can be done — taking action always feels good. And finally seeing the healthy plants with renewed vigor and growth is very rewarding to me!