Every great investigator has a knack for finding clues in the pursuit of solving a mystery. While sometimes searching for the signs and symptoms of plant pests comes naturally to many, others prefer to follow a process or answer a series of questions to properly diagnosis problems in the garden.
If being a garden investigator sounds interesting or tempting, but you need to know where to start, check out an OSU Extension FactSheet, The 20 Questions of Plant Diagnostics. It is available at your local Extension office or online at http://bit.ly/NRd6dk, and can be used to diagnose plant problems.
No matter the level of your experience, keeping notes can be helpful and provide a useful tool that you pull out each year to add to and review. An important tool every garden should have close at hand is a pen and paper. A garden-friend stored her pen and paper in a mailbox that was incorporated into her garden.
This gardener was able to jot notes, record observations, and list reminders when they were on her mind. Since it was in the garden, there wasn't a chance of forgetting something of importance that would have otherwise had to wait until she returned to the house — and in my case sometimes lost forever.
A walk through your garden may have you seeing some things that could appear to be problematic, but as time goes by, you will be able to have a better handle on which pests pose a serious threat, while others that can be lived with, and finally some that may be a natural bio-control.
So what do you see going on in the garden? Are there holes in the leaves? A quick turn of the leaf might give you some insight into the cause of the problem. Some insects feed primarily on the undersides of the leaves. Other insect pests could have come and gone; the damage is done and the insects aren't posing a current threat. Are there bumps or spots? These could be the result of a pathogen that could spread.
Pests that you might encounter this week include Japanese beetles, striped cucumber beetles, bean beetles, thrips, and aphids. While we have been dry, watering plant foliage can make way for some the diseases too. And don't forget that some of the insects you encounter are good guys, such as the lady beetles, lace wings, predatory wasps, and of course the pollinators. Mary Gardiner with OSU has created some useful ID Cards for gardeners. One of my favorites is the bee ID card — http://bit.ly/MXYiXH.
While diagnosing garden pests can be enjoyable, there are three challenges to consider when embarking on plant problem diagnostics in the garden or landscape:
? Some plant problems are obvious, while other problems are obscure.
? Some plant problems will not be diagnosed with a first effort. In fact, some plant problems may never be fully diagnosed.
? Gardeners usually want an immediate and clear-cut answer which produces great pressure to provide a quick-draw, clear-cut diagnosis.
Give it a try and enjoy the extra time in your garden just observing what is going on while enjoying that fresh tomato right off the vine. If you have a "stumper," contact your local Extension office for assistance in the identification. May your pests be minimal and your harvest be abundant this season!
Amy Stone is an Ohio State University Extension agent.