The October Dodge County Master Gardener Association meeting featured Gretchen Meyer, manager of the University of Wisconsin – Field Station, located at the Cedarburg Bog in Ozaukee County. She is an ecologist who studies the interactions between insects and their host plants.
Insects are the largest species group. 26% are phytophagous insects. Many are naturally beneficial through pollination and seed dispersal. Others are antagonistic through herbivory (insect eating plants) and carnivory (plant eating insects). 90% of flowering plants are animal pollinated; i.e., the transfer of pollen from anther to stigma. 30% of our human diet depends on animal pollination. Our Wisconsin state insect is a pollinator – the Honey Bee.
Herbivorous insects consume our food. Some examples include the gypsy moth and the Emerald Ash Borer. Insect herbivores are diverse. They include leaf chewers, leaf minors, sap feeders, and gall makers.
Plants have some defenses against herbivores:
- Grass blades with silica along the edge
- Stinging nettle has plant hairs that are toxic
- Bean leaves provide a remedy against bed bugs. The leaves have small hooked hairs on them to trap the bed bugs.
- Chemical defenses: secondary chemicals that we use as drugs and spices such as caffeine, nicotine, pepper, etc.
Insect herbivores counter-adapt to plants and are often specialized as with the Monarch Butterfly.
Carnivorous plants make up 1% of plants. Examples of carnivorous plants in Wisconsin:
- Butterwort: Found in one northern county
- Pitcher plant: Wisconsin bog
- Sundews: Round leaved and linear leaved sundews
- Bladderworts: Live in sluggish water areas
Venus flytrap is native to Carolina swamps.