Whether bugs have you aggravated because of the damage they cause to your garden or they just plain give you the creeps, have no fear! They aren’t all the menaces we think they are and some are downright beneficial. Although they may not be making their presence known in the dead of winter, this is the time to start taking the offensive approach to dealing with destructive pests. An ounce of prevention is worth a pound of cure!
Integrated pest management (IPM) is the best way to be proactive instead of getting caught off guard when the warmer weather hits. In simple terms, IPM is the practice of using multiple methods to manage pests with environmentally sound approaches. Not only does it take into consideration what effects our actions have on Mother Nature, but minimizing our health risks is also an element of IPM. This is not to say that pesticides should never be used, but they should not be the first line of defense in your battle of the bugs. Just keep in mind that as hard as we try, many damaging pests cannot be entirely eliminated.
One aspect of IPM that I find intriguing is biological control. It’s like assisting nature with curing some of its own ailments. The beneficial action of predators, parasites and pathogens can control pest damage, or at the very least minimize it. However, many of these assailants are highly specialized and attack only one or several closely related pest species (called hosts). By using a variety of them, you have a much better chance for success.
Did you ever think that bugs could actually be our allies? The “good bug / bad bug” relationship is just one element of IPM. Even small “good bugs” can be your frontline soldiers in the war against destructive pests. It’s not always easy to identify who is eating what, so be careful to distinguish the good and the bad guys before taking action. There are some great online resources that can help you with identification. The UC Davis IPM site is an excellent resource and the material is also in Spanish (http://www.ipm.ucdavis.edu/IPM).
Some of the destructive pests (bad guys) that can be attacked by natural enemies are: aphids, beetle larvae, giant whitefly, lace bugs, leafhoppers, mealybugs, psyllids, scales, spider mites, thrips, white flies and caterpillars (unfortunately that includes butterflies).
Common natural enemies who can destroy those destructive pests are: lacewings, lady beetles (including lady bugs), assassin bugs, parasitic flies (tachinid flies), syrphid flies (hover flies), parasitic wasps, predatory mites, soldier beetles, minute pirate bugs and damsel bugs.
So how can you allure these good guys to your garden? There are certain plants that are more likely to attract the beneficial pests and some actually repel the bad guys. However, a variety of plants are needed if you really want to be effective. Some of these natural enemies have different feeding requirements during various stages of their development (i.e.: nymphal stage to adult stage). Some examples of plants that attract beneficial insects are:
- Herbs: thyme, rosemary, coriander, dill, chives, oregano, sage, caraway, spearmint, parsley, mint, feverfew and tansy
- Perennials: fennel, angelica, queen Anne’s lace, yarrow, lantana, California fuchsia, purple cone flower, golden marguerite, native potentilla, butterfly weed, milkweed, spike speedwell, English lavender and some varieties of salvia
- Annuals: sweet alyssum, marigolds, carpet bugleweed and cosmos
- Crop plants: buckwheat, alfalfa, clovers and hairy vetch
Most spiders feed entirely on insects (good and bad) so sometimes they are actually our friends. I used to drive my family crazy when we lived in the Bay Area because I would be so excited when I found a spider in the house. I would insist that we would “trap and release” them and let them wreak havoc on the pests in my rosebushes.
Sometime in the next few weeks in this column, we’ll cover the rest of the biological controls arsenal-parasites and pathogens. Until then, have fun contemplating your bug-repellant strategies in the upcoming months.
Kathy Nunes is a new graduate of the Tuolumne County Master Gardener program. She was a Master Gardener in the Bay Area before moving here and isn’t afraid of bugs