Aphids can be hard to kill because they curl the leaves and you cannot get material 'onto' them. The good news is that insecticidal soap will kill them if the material reaches them. I would be diligent about expanding your leaves and exposing the aphids, then get them with insecticidal soap. Try this method. Aphid numbers are high this year due to high levels of moisture and new growth on trees, which they love.

Good luck.

Hello again...thank you for your reply!
Will insecticidal soap work on white flies as well?  I can barely stand next to my trees without stirring them up.  

Robin

Yes, soap will kill white flies too. It is a little odd to have white flies in your outside apple trees. We typically see these pests in greenhouses or enclosed spaces. I would recommend that you do some pruning next year to open your canopy in case there is too much shading and enclosed area that is allow white flies to flourish.

Nikki Rothwell