By: Chris Sumner


Growers should be on the lookout for soybean aphids as the insect has been found in several fields in southern Manitoba.

Parent Seed Farms agronomist Dennis Lange notes aphids can be found anytime of the day.

He adds the economic threshold is quite high, 250 aphids per plant and increasing.

If the decision is made to apply an insecticide, timing is critical.

Research has shown the best time to spray is in the early reproductive phase of the crop up to when you can feel a tiny bump when you run your thumb over the top pods.

Once the crop is in full seed, when the top pods have seeds in them that are swollen and filling the entire pod cavity, aphid numbers need to be much higher to see a yield response.