Scouting Pests Important Task for Farms & Gardens

The heat is on.  The projected temperatures in the next couple weeks are going to push plant growth in both fields and gardens & landscapes.  They are also going to push insect development and possibly open up opportunities for diseases to get into plants and cause damage.  Proper pest management on the farm or in gardens starts with knowing that the pest is present and having it properly identified.

The only way to find pests and identify them is to scout for them.  Spraying a pesticide to kill something that is already gone is a waste of time and money, as well as putting a chemical into the environment that has had no positive effects.  Likewise, spraying the wrong type of insecticide may give someone a false sense of security that they have taken care of the problem, but it doesn’t and gives the pest that many more days to wreak havoc.

On a farm, pest scouting is vitally important as it can make a huge difference as to the potential profitability in a given field.  Walking fields and surveying for insect presence, new weed species, or diseases can create the opportunity to save a crop from destruction or prevent many extra dollars from having to be spent when a pest gets worse.  A couple farm examples that are very tangible in our area:

– True armyworm is a caterpillar that is not extremely common.  However, when it does occur, it can cause nearly complete loss of small grains or corn fields if found in large enough numbers.  The last two years of wet conditions have created unplanted zones in the middle of some fields, which may have grasses growing in them that attract armyworm moths.  If a farm doesn’t see the beginning of this activity, they could lose acres of corn to a pest that they could have controlled fairly easily and with relatively small expense.

– Another example in crops is soybean aphid.  A much more common pest, but still only sporadically found in control-worthy populations.  If a farm automatically sprays to control aphids, but there were not enough present to merit the control method, they are spending money equivalent to 2 or 3 bushels of soybeans and not saving any yield.  On the flip side, not spraying when high populations are present can cut yield significantly, up to 20-30%.

In the garden or landscape, pests cause nearly as much mental anguish as financial harm, but proper pest management still starts with proper scouting.  Again, just a couple quick examples that help show the importance of properly identifying plant pests.  We are finishing the rose chafer/sand chafer/spring rose beetle season in our region, but beginning the time frame when Japanese Beetles may be found.  Many people confuse these beetle species, as they are similarly sized and Japanese Beetles are new to the area, still not being found in the northern two-thirds of Marinette County or the northern half or so of Oconto County.

If a home owner sees beetles feeding on a flowering shrub and assumes they are Japanese Beetles, they may start an insecticide program in which they spray every 7-10 days for the next 6 or more weeks.  However, if the beetles were actually spring rose beetles, their life cycle is coming to an end and insecticide applications may not do any good, and certainly would not merit more than one application.

You can probably think of many different examples of your own, as well.  Again, the key to properly managing pests is to know they are there and know what they are.  Then, you can make an informed decision that takes into account the pest’s life cycle and the full range of possible control methods.   If you are dealing with a plant pest that you can’t identify, you have the opportunity to contact Scott Reuss, Agriculture and Horticulture Agent for Marinette County.  If he cannot identify the pest, he has the full range of UW-Madison, Division of Extension resources to draw from to help diagnose the issue, as needed.

If you have any questions regarding particular plant problems you are facing, contact Reuss at or via phone at 715-732-7510.