By: Steve Jones, Scvrose@aol.com
Courtesy American Rose Society
Integrated Pest Management (IPM) is one method of pest control. Often called the
hybrid solution to organic and chemical sprays, the IPM program uses progressive
controls. Dale Bottrell, in his book, Integrated Pest Management, defines IPM as
"the selection, integration, and implementation of pest control based on
predicted economic, ecological, and sociological consequences. IPM seeks maximum
use of naturally occurring pest controls, including weather, disease agents,
predators, and parasitoids. In addition, IPM utilizes various biological,
physical, chemical control and habitat modification techniques."
The real basis of IPM is not the total annihilation of the pest that most of us
would hope for, but to control the pest population down to some acceptable
level. The reason is that if you tried to kill all the pests by chemicals, some
resistant individual pests will survive the holocaust of sprays and will
multiply into resistant varieties. Also, heavy use of pesticides will kill the
good as well as the bad bugs. In the long run, you have to maintain the desired
program if it is to function properly. IPM works in a progressive manner. You
start with the least harmful methods of control for man, animals, and the
environment collectively. The use of natural controls is the first item on the
list. If they fail, then you progress to controls with the least harm to man,
then to the least known to harm to animals and beneficial insects, and finally
the environment. Also in this process is consideration of cost effectiveness for
short and long term controls. No need for an expensive, labor intensive program
to remove a small percent of the population. As with any program, you need to
establish goals and define the parameters.
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What is the pest you are trying to control.
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At what level of reduction of that pest will you be happy?
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What environmental concerns do you have, etc.
So let's start with the pest itself. Have you properly identified it? Have it
identified by your local Ag Dept. or a local Consulting Rosarian. Once you have
identified the pest, learn all you can about its life cycle, stages of growth,
seasonal variations, where it winters over, etc. The more you learn of your
pest, the better you can control it. For example, in our area we have a beetle
called Hoplia. It is a member of the scarab family and closely related to the
Japanese Beetle. These beetles winter over as grubs in the foothills around us.
They become adults in late May and June, and fly to their feeding grounds. If
your roses are on their flight path, like mine, then they will not go any
further. They do a lot of damage to the lighter colored roses, but not as bad as
the Japanese Beetles. So since the life cycle occurs beyond my control, there is
little I can do about that control. They are active in late May and June,
normally when we do not have shows, so I am not as bothered by them and can
accept some damage. They have no natural predators or plants they find
offensive, so that is not an option either. My only recourse is to either ignore
them, hand-pick into a bucket of soapy water, or spray with an insecticide for
beetles, like Sevin®. I have tried white buckets of soapy water with little to
no success as well as the yellow sticky strips.
All of these methods, except for Sevin, are safe to the environment, pets, and
man. I have thought about placing a camouflaged cover over the roses but that is
a little extreme. By monitoring the seasonal patterns, I know when the Hoplias
are coming. You can do the same for all pests. Another example is that I do not
have to worry about mildew or rust in the summertime, as I am lucky to even have
roses in the 110 degree heat with low humidity. In the damp, cool spring and
fall powdery mildew is a problem, so I have to start controls before those
times. With most things, it is easier to prevent problems than to play catch-up
once the problem becomes established. One requirement for a good IPM program is
monitoring and recordkeeping. Keep track of what you did, when you did it, and
the level of control, if any. Also note any damage to the plant or surroundings
due to the control method. Set some parameters on what to look for when you
monitor. If you see a couple of aphids - that may be okay, but if you see a
mass, then it's time to spray or release more ladybugs, especially if there are
few ladybugs around. So your level of monitoring can be looking for signs of the
pest, pest levels, predator levels, and signs of damage from the pest or control
method. It is a good idea to monitor your program each time you are in the
garden. It doesn't have to be a scientific study each time, just glance around
your roses and note anything good, bad, or indifferent. IPM programs can be
short or long term. Short term programs will take care of the problem at the
minute, and will not control long term. One application of a pesticide will work
for a short time, while the planting of offensive plants to the pest are long
term. Other long term measures could be relocating the desired plants away from
potential sources of the pest, installing fences to keep the pest out (such as
deer) or to include plants that attract natural predators. A good rule to follow
is to remove all potential sources of the pest. Fungus spores hide on leaves so
remove all the refuse from the ground. Keep your rose beds clean at all times.
Water works wonders for cleansing leaves in dry areas to help control mildew and
spider mites. Biological controls take many forms and shapes. We all know that
ladybugs and lacewings will eat their fair share of aphids. There are bacteria
that are commonly used to control certain types of caterpillars. Parasitic wasps
are used to control white ash flies and many caterpillars. These may be locally
occurring predators or they can be imported. There are several levels of control
even for chemicals. There are some natural occurring materials such as
pyrethrins, and there are "sex" attractants, to lure the pest to the control
material. Once you have exhausted all of these controls with no success, then
you proceed with chemicals. In any IPM program, there is no right or wrong way.
You may have several types of control working at one time, from perfectly safe
to chemical sprays.