Now that you’ve become a pro at figuring out what’s bugging your roses, your next choice is what to do about it. If you’re interested in using the least toxic remedy to your problem, consider using an integrated pest management (IPM) approach. According to the U.S. Environmental Protection Agency (EPA), IPM is “an effective and environmentally sensitive approach to pest management that relies on a combination of common-sense practices. IPM programs use current, comprehensive information on the life cycles of pests and their interaction with the environment. This information, in combination with available pest control methods, is used to manage pest damage by the most economical means, and with the least possible hazard to people, property, and the environment.”Determining how much damage you can tolerate
Observing the garden for pests
Identifying the culprits
Developing your control approach
In this series of articles, we’ve covered the first three components; now it’s time to look at options for pest control.
An IPM approach for pest or disease control is progressive – like the diagram on the right. Initial pest management measures employ the least toxic method - cultural, and if not adequate, proceeds to mechanical, biological and finally, chemical options. Control is attempted at each one of these levels with progression to the next, more toxic method if the level of desired control is not achieved or the level of damage is not tolerable.
Cultural control methods include selecting plants with known disease resistance, maintaining healthy and vigorous plants through proper choice of planting location and care practices - watering, fertilizing, pruning, mulching and good garden hygiene.
Handpicking or hosing insect pests off roses are examples of mechanical control methods as are physical barriers like fencing for deer, planting in wire for protection against gophers, rolled newspaper traps for earwigs or spraying with anti-transpirants for fungal diseases.
Improving habitats for beneficial insects such as ladybugs, green lacewings, birds, lizards and toads are examples of simple biological control measures; more elaborate methods may include introducing pheromones to attract natural enemies, using BT (Bacillus thuringiensis) or other microbes to infect and kill unwanted pests.
If you elect to use chemical methods, start with the least toxic products like horticultural oils, insecticidal soaps, neem seed extracts and pyrethrum - organic chemicals that can be used selectively. Avoid broad-spectrum chemicals that kill everything it’s sprayed on. These types of products can actually result in increased pest populations by eliminating beneficial creatures.
Once you get into the habit of it, IPM is really quite easy and makes lots of environmental and economical sense. It is good for your roses, your garden, pets, and people.
Photo of rose stem girdler larvae courtesy of University of Minnesota Entomology website
Photo of rose stem girdler damage courtesy of Missoula Montana Extension Plant Services website
All other photos courtesy of Baldo Villegas’ website at http://buggyrose.tripod.com/irosepests.htm<