In a 2022 Coffee and Pest Management webinar, Dr. Laura Ingwell, an Assistant Professor in Horticulture Entomology at Purdue University, described Integrated Pest Management for three different pests. Dr. Ingwell takes a look at cabbage worms, aphids, and cucumber beetles.
If you want to learn more about our “Coffee and” webinars, be sure to check the page on our website. Learn more about our Urban and Small Farms Program to see if you are eligible for free soil testing and other services.
Integrate Pest Management (IPM) is an “ecosystem-based strategy that focuses on long-term prevention of pests and their damage through a combination of techniques.” IPM uses variety/cultivar selection, timing, location, habitat manipulation, biological controls, and as a last result, pesticides to manage the pests in your farm and garden.
Cabbage worms go through complete metamorphoses. Larvae are the dangerous form of this insect to our plants. The bigger the larvae get, the more they eat the plant. Once they complete their larval stage, they go through a pupal phase where they make the transition to adulthood. After the adults mate, they lay eggs. The best way to manage cabbage worms is preventing the adults from laying eggs on your plants. If you’re too late, you can address them as small caterpillars.
Crop selection can be used to prevent cabbage worms. Take notes and see which crops are chewed most in your garden, avoid planting those the following year. Another tool is exclusion. Use low tunnels to add a physical barrier keeping the moths from making contact with your plants. Biological controls such as tachinid flies, parasitic wasps, and predatory stinkbugs are natural enemies to cabbage worms. Chemical controls are a last resort, but foliar sprays of Bt are an effective organic option.
Aphids are small and sneaky. They feed on plants with a sucking mouthpart much like a straw. They can kill seedlings and young transplants and vector plant viruses. Thier direct feeding on plant sap results in excess sugar that the insect excretes in the form of honeydew. The honeydew attracts other insects, like ants, wasps and bees, and also facilitates the growth of sooty mold, a black-white powdery substance which inhibits photosynthesis. Aphids undergo incomplete metamorphosis. The juveniles look like miniature versions of the adults. They also give live births, so you won’t find any eggs. There are both winged forms, for long distance dispersal, and wingless forms. Cultural controls include monitoring your plants and the plants around them for the presence of aphids and their natural enemies. Biological controls include parasitic wasps, lacewings, ladybeetles, minute pirate bugs, and syrphid flies. If natural enemies are present, just monitor the population to see if they continue to build or remain the same/decline. If cultural and biological controls fail, chemical controls are a last resort. Horticultural soaps and oils can be effective in a home garden setting.
There are two different species of cucumber beetles: striped and spotted. Striped cucumber beetles only feed on cucurbits, whereas spotted cucumber beetles are not as picky. All of them can transmit a bacterium that leads to bacterial wilt. There are two peak times during the growing season when adults are present and transmitting the disease – early spring when they are looking to feed and lay eggs and, in the late summer, when the second generation is preparing to overwinter in the soil. A major portion of their lifecycle takes place in the soil. Cultural controls include delayed planting. Waiting to plant any cucurbits in the spring prevents the adults that overwintered from finding food when they emerge from weedy habitat where they have overwintered. Mechanical controls include exclusion with a screen that will allow small beneficial insects in but not cucumber beetles. Spiders are a great biological control. Chemical controls such as foliar sprays and powders can be used but only as a last resort.
If you want to learn more about IPM other resources include the Purdue Consumer Horticulture website, the Purdue Entomology Extension Vegetable Website, the Purdue Entomology Extension Fruit Website, and the Purdue Plant and Pest Diagnostic Laboratory.
Where does your food come from? Many students across Indiana give the answer “the grocery store.” Although this is often true, the grocery store is not the starting place of our food. Farm Bureau’s Agriculture in the Classroom Program works with kids around Indiana teaching them about the origins of their food and why farmers are important. Through this program, Farm Bureau holds summer workshops for teachers and volunteers giving them ideas about how to teach agriculture in their hometown school systems.
The Allen County Soil and Water Conservation District had the opportunity to participate and lead a couple of sessions in one of the Agriculture in the Classroom workshops on June 1st at Huntington University. Mike Werling, a farmer and part time employee with the Allen County SWCD, lead a workshop on managing erosion. Erosion is a menace that has plagued agriculture for millennia. Werling used the slake test, a homemade rainfall simulator, and a purchased rainfall simulator to demonstrate different ways teachers can educate about soil health and erosion control in their own classroom.
The slake test shows the structural difference between soil in a no-till situation and soil in a tillage situation. It utilizes two class cylinders filled with water. Mesh wiring drapes like a hammock from the top of the cylinders and submerges in the water. For this demonstration, you must have two different dried peds of soil. One ped should be from a no-till field and the other from a tilled field. When the aggregates are submerged into the water and placed on the mesh wiring, the audience can see the difference between the tilled soil and the soil from a no-till field. The no-till ped will hold together, but the soil from the tilled field will break apart easily in the cylinder. Check out this video of a slake test!
The homemade rainfall simulator can be made out of 3 plastic, two-liter bottles with 1/3 of the plastic cut out of the side. One of the bottles should contain nothing but bare soil. The second bottle should be filled with soil, but covered with residue like straw, leaves, or sticks. The third bottle should contain growing cover crops (clover, annual rye, cereal rye, oats, etc). Water is then poured over the two-liter bottles. The bottle with bare soil will lose the largest amount of soil to erosion, the soil with a residue will lose significantly less soil because of the residue, and the cover crop soil will lose the least amount of soil when “rain” is introduced to it. Check out this video of a two-liter bottle simulator!
The purchased rainfall simulator works very similarly to the homemade version. Watch this video to see how a rainfall simulator works!
The Allen SWCD also shared a lesson on watersheds and water quality. Joelle Neff used an Enviroscape to teach about how water moves downhill and picks up pollutants in a watershed. Neff also taught a lesson called “Growing with Water” which uses data collected from the Water Quality Initiative Program to discuss why pollutants have varying impacts at different times in the year.
An Enviroscape is a model of a watershed landscape that funnels water into the landscape’s reservoir. The model has a farm, factory, nature preserve, golf course, construction site, neighborhood, water treatment facility, roads, and ditches. Pollutants such as fertilizers, pesticides, human and animal waste, oil, road salt, etc are introduced to the landscape. Simulated rain is then applied to the landscape. Students are able to see all the pollutants that have entered the reservoir after the rain. This tool has fairly easy clean up. You can remove the plug in the reservoir to drain water into the basin below.
Like mentioned earlier, “Growing with Water” uses data collected from the Fort Wayne Water Quality Initiative Program which has been collecting water samples weekly in Northeast Indiana and Northwest Ohio since 2002. Check with your local Soil and Water Conservation District (SWCD) to see if collect water samples in your area. “Growing with Water” teaches students about the quality of water in their area and the different pollutants that can impact their water systems. Growing with Water shows the variances of water quality in different seasons. Split your class into three different groups: spring, summer, and fall. Have each group come up with a list of what is happening in agriculture and with the weather in their season. Then, provide students a tracking sheet with the percentage of time that the pollutants were higher than they should have been. Have the students work in their groups to make hypotheses about reasoning for the pollutant levels based off what is happening in their season.
If you would like to use any of these demonstrations to teach in your classroom, give the Allen County SWCD a call at 260-484-5848 ext. 3.
Soil testing is a valuable way for farmers, gardeners, and those with lawns to know what nutrients are already available in their soil, as well as what nutrients should be added. Not knowing what is already available in your soil, makes it easy to over-apply or under-apply fertilizers. Over application can cause negative impacts on water quality if runoff transfers the excess nutrients to waterways. Having too few nutrients in your soil can impede plant growth.
No matter what you’re growing, getting a soil test is important!
On Friday, May 14th, the Allen County SWCD and Purdue Extension partnered to teach soil testing to the first grade students at Washington Elementary School in downtown Fort Wayne. The students did an excellent job listening!
The class learned the importance of getting a soil test. Their faces lit up as they answered questions about how we can protect our water systems by keeping excess nutrients out of them. Excitement filled the school grounds as teachers, students, and agency staff chose different locations to collect soil samples. Each student was able to pick a sampling location.
The first graders not only learned about soil testing, but they also learned about the different textures of soil. Students felt examples of sand, silt, and clay, as well as play a game that taught them the different properties of these textures. Sand is the largest particle with lots of surface area. It feels course when rubbed between your fingers. It allows for good drainage and doesn’t hold water or nutrients very well. Silt is the medium-sized particle. It feels smooth like baking flour when wet. It doesn’t stick together, so it still has good drainage, but it is small enough to hold water and nutrients. Clay is the smallest soil texture. It sticks together when wet, giving it a sticky texture. Much of the soil in Northeast Indiana has a heavy clay content. Clay does not drain water easily, sometimes remaining waterlogged and causing root rot in plants. On the other hand, clay soils are excellent at holding nutrients.
If you knew all this, congrats! You are smarter than a first grader, but don’t stop there! Keep learning about Conservation Practices like soil testing.
This demonstration was sponsored by the Natural Resources Conservation Service (NRCS) through our Urban and Small Farms Program. The USDA is an equal opportunity provider and employer.