Aphid infestation/tree identification

Niamhtreacy

Hello,

This is our first spring in our rented property. We've just started giving some much needed care to the garden. Out neighbour has informed us of a bug infestation that comes from one our trees. It seems to have started (pictured) and we believe it is blackfly aphids. I have already seen them on some of my newly planted flowers. Would you recommend we cut the tree they're feeding off down? And can anyone identify the tree?

If I do cut it down, will this cure the infestation or will the eggs still be in the soil and attach to something else? It's breaking my heart to see new flowers ruined. 

BobTheGardener

It looks like an elder (elderberry) tree which are infamous for getting blackfly infestations.  It's a good tree for wildlife but also can be considered a weed species when it self-seeds into the wrong places (eg smaller gardens) so I wouldn't worry about cutting it down.  Aphids have an interesting life cycle but can develop flying forms which start colonies on other plants and ants carry the young around to other areas as they feed off of the sugary substance aphids excrete.  There won't be eggs in the soil and the majority of blackfly are flightless so won't move from the cut-down tree onto other things.

nick615

If you want to kill the blackfly (or greenfly), boil some rhubarb leaves, drain off the fluid, put it in a trigger spray bottle (any saved from the kitchen will be ideal) and spray the aphids with it.  Watch them fall off but beware, the liquid is very poisonous to humans!