Keeping a journal is one of the best ways to make sure this year’s problems do not plague you next year.
Record the date, the type and extent of damage, the plants affected, any pests seen and how you dealt with the problem.
If there are diseases you will want to note the type, and conditions, so you can avoid them in the future.
Keep a record of natural enemies you have observed, or not. You can make habitat changes if you aren’t attracting or keeping helpful insects for your garden.
If you are motivated, look up your pests on the internet and save a picture for future reference.
You can review your records in the years to come to know the warning signs of damage and particulars of the specific pests you already encountered.
A great resource for identifying insect pests is provided by Texas A&M University. While it focuses on vegetables, many of the same pests attack other garden and landscape plants and flowers. A good website identifying least toxic materials is provided by IPM Access - An Integrated Pest Management Online Service
Disclaimer: Federal EPA Regulations declare that the label is the law! Pesticide users are forbidden to use a pesticide in a way contrary to labeling. Please read the pesticide label prior to use. Any use not indicated on the label is prohibited. State and local laws may be more stringent than federal requirements so check with your local jurisdiction for regulations.
An excellent resource on natural enemies is provided by Cornell University. It details the four classes of natural enemies, with pictures and descriptions. Over 100 insect helpers from North America are profiled.
EMBO Reports: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1084120/
US EPA: http://www.epa.gov/opp00001/factsheets/ipm.htm
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