Gardener’s Corner

     Now is the time of the season to prepare for the devastation that the Japanese Beetles will cause next spring.  Look back at the article I wrote concerning grubs in the spring.  There is a “beautiful” picture of the grub damage that was prevelent last spring.  It may seem odd, but just like you have to plant bulbs in the fall to get spring flowers, you have to think about controlling the beetle/grub population now to prevent damage in the spring.  Let’s look at the life cylce of the Japanese beetle.  The adults usually emerge in June and July.  Their purpose in life at this point is to eat and mate.  Unfortunately for us they don’t have a specific plant they go after.  They are happy to eat around 300 different types of plants.  So controlling the adults is difficult.  The females are happy to mate with many different males as well.  After the female mates she will burrow into the soil 2-4 inches and lay 1-5 eggs.  After laying the eggs she will go back to munching and mating.  This cycle continues until she has buried between 40-60 eggs.  In 17-25 days the eggs will hatch into a C shaped white grub.  The grubs are enjoyed by crows and skunks and unfortunately they will tear up your lawn looking for them.  It is easiest to control the grubs at this young stage.  Applying a grub control with Merit in it will make the grass roots poisonous to the grubs and kill them. 

     If the adults are chewing up your garden you can also spray them with an insecticide.  You will have to spray on a regular basis because the adults keep emerging all through the summer months.  Phermone traps are not recommended because they bring hordes of beetles into your garden.  It is better to not trap at all, or give the trap to your neighbor so the beetles visit their garden instead.  To identify the beetle look for a beautiful metallic green bug eating your plants.  There is only one other beetle that looks like the Japanese beetle and that is the False Japanese Beetle.  The way you can tell the difference is to look at the hair tufts along the abdomen.  The Japanese Beetle has them making it look like they have 5 white dots on the side of their body.

Happy Scouting!

Phenlogy is a study in the correlation between bloom times, degree days, and insect emergence.  It is very useful in IPM.  IPM is integrated pest management.  Integrated pest management is the practice of using biological controls, cultural practices and chemicals to control detrimental insects in your garden with out doing to much damage to the beneficial insects. It excludes the use of blanket sprays which kill everything in their path.  Why are we interested in protecting beneficial insects?  Mostly because we beneficial insects help us out by controlling the detrimental insects and doing the work of pollinating.  Never heard of beneficial insects?  There are lots of the them out there.  Some examples are, Praying mantis which feeds on  insects including aphids.  Lady bugs which are cute and also feed on aphids, and adelgids.  Honey bees which of course pollinate our fruits, vegetables and flowers while making that delicious golden treat we call honey.  There are many important beneficial insects in this world that we simply can not do without.  Phenology helps us to pin point which insects are hatching at a certain time so we can time our chemical sprays to not only protect the beneficial insects, but also kill the detrimental insects at the most opportune time.  An example of this is scale.  Scale insects have a hard shell during the adult phase of their lives, that protects them from weather, chemicals and other predatory insects.  When the young hatch out from beneath this protective cover, it is called the crawler stage. During the crawler stage they are moving around on the plant looking for a place mate and then become a sessile adult with a hard shell.  The most vulnerable time to spray for certain scale insects like Magnolia scale is right now during the crawler stage.  Phenology helps us to determine when that crawler stage is by linking it to something that is easy to see, for example, right now Oakleaf hydrangea, butterflyweed, Greenspire Linden and Queen of the Prairie are blooming. The bugs associated with those blooms are Magnolia scale, Rudbeckia (Black Eyed Susan) psylids, Sycamore lacebugs and Japanese beetle (the adults are out).  Having this information at your fingertips will help you to not only spray when needed but diagnose what may be causing problems in your garden.  Remember we want the good insects and not the bad.  The good insects will help us control the bad. For more information on phenology you can use the internet and Google phenology.