Header photo of a Thick-legged Hover Fly, Syritta pipiens (family Syrphidae) is foraging on a flower of California Buckwheat. Photo credit: May Chen’s Pollinator Posts.
Article written by SPAWN’s Nursery Manager, Kristen Hopper.
Ever wonder what to do about that snake under the deck, or the leaf curl on your favorite perennial? When people ask me questions about pests, whether it be un-nerving reptiles, piercing insects or fungal infections, my thoughts usually turn to the idea of Integrated Pest Management. This framework for managing pests in the least toxic way possible begins with observation and monitoring. That is, understanding what you are seeing and deciding what is a tolerable threshold. How many snakes are too many? How much of this piercing insect can I tolerate?
In the larger context of recognizing our home gardens and landscapes as habitat for all of us biological organisms, we begin to see that there are important connections between organisms. Once we can identify the snake as non-venomous, we may decide that its services reducing the mouse population around the home may make it a tolerable addition to an outdoor space. On the other hand, if the home owner has a deep fear of snakes, maybe that garter or gopher snake and its family should be moved on – hopefully somewhere away from the home and possible harms from living close to the road.
As to the piercing insects such as aphids, pull up a chair and spend some time observing them, you will soon see some interesting interactions. Aphids are often tended by ants. The ants act as aphid bodyguards while benefiting from their apparently yummy (to an ant) excretion known as ‘honeydew’. Watching this weird bit of animal husbandry for a while, you will then begin to notice that there are other insects making the rounds avoiding ant bodyguards and feeding on the aphids. These important predators of aphids (and other insects feeding on plant tissues) are called beneficial insects.
Beneficial insects are important in helping keep plant chomping insects at bay, but they are also in turn part of the food web, eaten by other larger insects or insectivorous birds and small mammals. If say the aphids seem to be getting the upper hand and the infected plant seems to be losing vigor, then choosing a least toxic control method would likely begin with a physical approach (e.g. the use of a garden hose to spray the plump little plant suckers off).
Physical removal to reduce the aphid population will help keep the other beneficial insects in business because there will still be plenty of food for them and you have avoided harming an important part of the ecosystem by choosing not to take control methods to the next level. Deploying chemical controls can have unintended effects. It may provide a reprieve for your favorite perennial but kill off the beneficial insects as well. Of course we need the beneficial insects. To support the beneficials including pollinators it is always important to ask if we can tolerate a bit of plant predation and the company of non-venomous snakes.
If you like the idea of pulling up a chair and watching the busy life of insects, check out May Chen’s Pollinator Posts here! To learn more about gardening for wildlife, dive in to SPAWN’s resources here.
