Attracting and Utilizing Beneficial Insects
There is lots of buzz lately about the plight of insects, especially bees. Market gardeners have it tough. It is difficult to balance the needs of farming with the demands of consumers. We have only to look to the argument over GMO’s to see the backlash from the public. That is one of the reasons that organic food is growing by leaps and bounds — the end consumer is driving the market. Attracting and utilizing beneficial insects is not just a whimsical idea it is an idea that can drive marketing campaigns and attract consumers to your products. In this market farming and flower blog, we explore the needs of insects and provide a few insights into organic means of benefiting from beneficial insects.
Predator or Prey?
The insect world, in its simplest form, can be divided into two groups. Those that prey upon other insects and those that do not. As we begin the discussion about beneficial insects, it becomes important that we define what the word beneficial means. For farmers, “beneficial” should mean the insect provides a service that improves crop yield. This could be as simple as attracting pollinators. However, for flower farmers, pollination is not a huge concern since they are harvesting the flower. An example of a beneficial insect for flower farmers is one that preys upon insects that consume flowers or flowering plants. The challenge for organic farmers is attracting beneficial insects to their gardens at just the right time.
Time is an important consideration because insects are present all year long. We may not notice that there are beetles on the farm. We may not notice that there are butterflies in winter. The reason being is that insects change shape. Their life cycle ranges from an egg to a larva, and onwards to an adult. Some insects, those that have a complete lifecycle also pupate before becoming an adult. So just because we do not see butterflies in winter, they are still present as a chrysalis in their pupal form. The same is true of pests. So pest control for small farms should include consideration of time and form of insects.
Pollinators — There Are more Available than Just Honey Bees.
Native bees are a huge and often untapped labor force for market gardeners and flower farmers. The reason we don’t hear a lot about them is because they are solitary and ground nesting. That means when you till up your land you destroy their nests. An easy solution to this problem is a hedgerow. A hedgerow is typically a row of native plants and shrubs which may be pruned but not removed. In the ground, around the roots native bees create nests. There is a lot of research available on the benefit of hedgerows and pollination and an equal amount of research that discusses how hedgerows help decrease pests. UC Berkeley has a good resource for learning more about hedgerows and farming.
Pest Control for Non-pollinators.
Insects are remarkable, but they are also difficult to use as tools. The natural cycle of life is such that without an explosion of pests you will likely not ever has an explosion of predatory insects. Ladybugs are a prime example. Even when we buy them for pest control they tend to disappear shortly after we release them. This is because insects operate based on pheromones and when we capture ladybugs they are almost always in a dispersal mode. This is why they fly away. Biological controls do help and we use insects in that capacity. A good example of a biological control is the praying mantis. These can be purchased as egg cases and then distributed around your farm. As you think about ladybugs and mantids understand that time is still a key consideration. Mantids are typically out in mid-summer and gone by late fall. They are also not pest-specific. They happily eat anything they can catch from hummingbirds to bees. They are also fairly worthless on small insects such as aphids. That means that pest control has to be a conscientious process. The predator needs to match the prey in terms of size and emergent timing. Fortunately, insect predators come in all sizes. Take the parasitoid wasps which range from tiny 1mm to beasts that hunt and battle tarantulas. There are biological controls for many insect pest problems. Here is a list of biological control insects used in New Zealand as an example.
The big question for market farmers is what’s bugging you?
David Stillwell is an organic gardener, entomologist, writer and student. He specializes in hymenoptera – bees, wasps, and ants, and the study of cecidology – Plant galls. He has a fondness for recognizing natural circles and energy webs that exist in nature — those interconnected natural systems such as food webs. He is a native of California and an advocate for conservation, locally grown, and farmer’s markets.
The Featured Image above is a Papilio rutulus – The Western tiger swallowtail – A beautiful and helpful pollinator – Photo credit: David Stillwell