Question
I live in Oakville, Ontario just 30 minutes west of Toronto in zone 6a or 6b. I just planted a 15 foot Tricolour beech a month or so ago and this last week or so, I noted as the weather has been getting warmer, that on the underside of some of the leaves, there is white, kinda fluffy stuff.  I don't know what it is...can you help me identify this, please. I noted some very tiny lime green teeny bugs yesterday. I was told this is a spider mite of some kind. Is this a pest that was in the tree when I bought it (it had no leaves when it was purchased)? What is it and how do I rid the tree of its spread? It is spreading fast and I can't even reach the top branches. I sprayed it yesterday with an Insecticidal soap and wiped down as many leaves as I could reach and repsrayed it again once finished. thanks for your advice.
Jan

Answer
These are aphids (an insect) and what you are doing will kill the insects. The treatment should be repeated once a week. Some aphids are not killed by the soap so you may have to spray the tree with an insecticide--one called Orthene is a good systemic insecticide and will work well on aphids.