As many of you know, the buzz in soybeans the last few weeks has been about aphid populations. Throughout southwestern Ontario aphids have been approaching, or in many cases exceeding thresholds in many fields.
The threshold in aphids is 250 per plant which is not hard to find. A component to this happening could be a Potassium deficiency in the plant. There seems to be a correlation to Potassium deficiency and “sucking” insects. When the K level in the plant is high or sufficient there seems to be less of these sucking insects and as we all know, K levels in soils in Ontario have been dropping over the last 10-15years. This could by why there seems to be more aphids in stressed areas of the field. The answer in most cases is for an insecticide application to control these pests which most times means another pass with the sprayer. There is a good thing that can come out of this late pass with the sprayer though! At the current staging of soybeans for the most part, this timing of the sprayer makes it a great time for some late season foliar fertility. At Alpine we have a great line of foliars that can help push for those extra bushels. One product that I would recommend goes in with the insecticide is our new ALPINE K20S product which can give the soybeans Potassium for pod fill and Sulphur as well as some micronutrients such as Boron(can help produce and retain flowers on the plant) and Manganese. We have seen great results with this product in the past and mixes well with most insecticides but as always it is a good idea to do a jar test if there is any doubt. Any questions on this or any other product in our line up feel free to contact an Alpine DSM or talk to one of our dealers.
– Nick